Apparatus and method of random access precedure

ABSTRACT

A communication method and system for converging a fifth generation (5G) communication system for supporting higher data rates beyond a fourth generation (4G) system with a technology for Internet of things (IoT) are provided. The communication method and system may be applied to intelligent services based on the 5G communication technology and the IoT-related technology, such as smart home, smart building, smart city, smart car, connected car, health care, digital education, smart retail, security and safety services. A method for performing a random access procedure in a wireless communication system is provided.

CROSS-REFERENCE TO RELATED APPLICATION

This application is based on and claims priority under 35 U.S.C. § 119to U.S. Provisional Patent Application No. 62/961,103, filed on Jan. 14,2020, in the USPTO, the disclosure of which is incorporated by referenceherein in its entirety.

BACKGROUND 1. Field

The disclosure relates to an apparatus and a method of performing randomaccess procedure.

2. Description of Related Art

To meet the demand for wireless data traffic having increased sincedeployment of 4G communication systems, efforts have been made todevelop an improved 5G or pre-5G communication system. Therefore, the 5Gor pre-5G communication system is also called a ‘Beyond 4G Network’ or a‘Post LTE System’. The 5G communication system is considered to beimplemented in higher frequency (mmWave) bands, e.g., 60 GHz bands, soas to accomplish higher data rates. To decrease propagation loss of theradio waves and increase the transmission distance, the beamforming,massive multiple-input multiple-output (MIMO), Full Dimensional MIMO(FD-MIMO), array antenna, an analog beam forming, large scale antennatechniques are discussed in 5G communication systems. In addition, in 5Gcommunication systems, development for system network improvement isunder way based on advanced small cells, cloud Radio Access Networks(RANs), ultra-dense networks, device-to-device (D2D) communication,wireless backhaul, moving network, cooperative communication,Coordinated Multi-Points (CoMP), reception-end interference cancellationand the like. In the 5G system, Hybrid FSK and QAM Modulation (FQAM) andsliding window superposition coding (SWSC) as an advanced codingmodulation (ACM), and filter bank multi carrier (FBMC), non-orthogonalmultiple access (NOMA), and sparse code multiple access (SCMA) as anadvanced access technology have been developed.

The Internet, which is a human centered connectivity network wherehumans generate and consume information, is now evolving to the Internetof Things (IoT) where distributed entities, such as things, exchange andprocess information without human intervention. The Internet ofEverything (IoE), which is a combination of the IoT technology and theBig Data processing technology through connection with a cloud server,has emerged. As technology elements, such as “sensing technology”,“wired/wireless communication and network infrastructure”, “serviceinterface technology”, and “Security technology” have been demanded forIoT implementation, a sensor network, a Machine-to-Machine (M2M)communication, Machine Type Communication (MTC), and so forth have beenrecently researched. Such an IoT environment may provide intelligentInternet technology services that create a new value to human life bycollecting and analyzing data generated among connected things. IoT maybe applied to a variety of fields including smart home, smart building,smart city, smart car or connected cars, smart grid, health care, smartappliances and advanced medical services through convergence andcombination between existing Information Technology (IT) and variousindustrial applications.

In line with this, various attempts have been made to apply 5Gcommunication systems to IoT networks. For example, technologies such asa sensor network, Machine Type Communication (MTC), andMachine-to-Machine (M2M) communication may be implemented bybeamforming, MIMO, and array antennas. Application of a cloud RadioAccess Network (RAN) as the above-described Big Data processingtechnology may also be considered to be as an example of convergencebetween the 5G technology and the IoT technology.

SUMMARY

Aspects of the disclosure are to address at least the above-mentionedproblems and/or disadvantages and to provide at least the advantagesdescribed below. Accordingly, an aspect of the disclosure is to providea communication method and system for converging a fifth generation (5G)communication system for supporting higher data rates beyond a fourthgeneration (4G) system.

According to an embodiment of the present disclosure, a method performedby a terminal of a random access procedure for a small data transmissioncomprises receiving, from a base station, at least one synchronizationsignal block (SSB), identifying at least one preamble associated withthe at least one SSB based on first information on a number of preamblesper SSB and second information on a starting index, for one of a 4-steprandom access procedure or a 2-step random access procedure for thesmall data transmission, selecting a preamble from the identified atleast one preamble corresponding to an SSB selected from the at leastone SSB, and transmitting, to a base station, the selected preamble in aphysical random access channel (PRACH) occasion corresponding to theselected SSB.

According to an embodiment of the present disclosure, a method performedby a base station of a random access procedure for a small datatransmission comprises transmitting, to a terminal, at least onesynchronization signal block (SSB) and receiving, from the terminal, apreamble for one of a 4-step random access procedure or a 2-step randomaccess procedure for the small data transmission, in a physical randomaccess channel (PRACH) occasion corresponding to an SSB among the atleast one SSB, wherein at least one preamble associated with the atleast one SSB is identified based on first information on a number ofpreambles per SSB and second information on a starting index for one ofthe 4-step random access procedure or the 2-step random access procedurefor the small data transmission and the preamble corresponding to theSSB is selected from the at least one preamble.

According to an embodiment of the present disclosure, a terminal of arandom access procedure for a small data transmission comprises atransceiver and a controller coupled with the transceiver and configuredto control to receive, from a base station, at least one synchronizationsignal block (SSB), identify at least one preamble associated with theat least one SSB based on first information on a number of preambles perSSB and second information on a starting index, for one of a 4-steprandom access procedure or a 2-step random access procedure for thesmall data transmission, selecting a preamble from the identified atleast one preamble corresponding to an SSB selected from the at leastone SSB and transmit, to a base station, the selected preamble in aphysical random access channel (PRACH) occasion corresponding to theselected SSB.

According to an embodiment of the present disclosure, a base station ofa random access procedure for a small data transmission comprises atransceiver and a controller coupled with the transceiver and configuredto control to transmit, to a terminal, at least one synchronizationsignal block (SSB), and receive, from the terminal, a preamble for oneof a 4-step random access procedure or a 2-step random access procedurefor the small data transmission, in a physical random access channel(PRACH) occasion corresponding to an SSB among the at least one SSB,wherein at least one preamble associated with the SSB is identifiedbased on first information on a number of preambles per SSB and secondinformation on a starting index for one of the 4-step random accessprocedure or the 2-step random access procedure for the small datatransmission and the preamble corresponding to the SSB is selected fromthe at least one preamble.

Additional aspects will be set forth in part in the description whichfollows and, in part, will be apparent from the description, or may belearned by practice of the presented embodiments.

For random access procedure, upon receiving the random access preamble,gNB needs to identify whether the UE has initiated the random access forsmall data transmission or not. In an UL BWP, 4S RA (4-step randomaccess) for SDT and/or 4S RA for Non SDT and/or 2S RA (2-step randomaccess) for SDT and/or 2S RA for non SDT can be configured. ROs may ormay not be shared between one or more of these RA types i.e., 4S RA forSDT, 4S RA for Non SDT, 2S RA for SDT, 2S RA for non SDT. The issue ishow to determine which preambles/SSB/RO are used for 4S RA SDT and 2S RASDT. Explicitly indicating each preamble index for each SSB/RO will leadto significant signaling overhead.

For sidelink communication, UE can be configured with both scheduledresource allocation (i.e., Mode 1) and autonomous resource allocation(i.e., Mode 2) scheduling modes. gNB indicates scheduling mode (Mode 1or Mode 2) associated with each SL LCH. UE multiplexes SL LCH(s)associated with same scheduling mode in SL MAC PDU. This approach maylead to wastage of resources. Some mechanism to multiplex SL LCHassociated with a scheduling mode in SL grant of another scheduling modeis needed.

The embodiments in this disclosure describe methods to determinepreambles/SSB/RO are used for 4S RA SDT and 2S RA SDT for various RAconfigurations with minimum signaling overhead.

The embodiments in this disclosure also describe methods to multiplex SLLCH associated with a scheduling mode in SL grant of another schedulingmode to reduce resource wastage.

Other aspects, advantages, and salient features of the disclosure willbecome apparent to those skilled in the art from the following detaileddescription, which, taken in conjunction with the annexed drawings,discloses various embodiments of the disclosure.

Before undertaking the DETAILED DESCRIPTION below, it may beadvantageous to set forth definitions of certain words and phrases usedthroughout this patent document: the terms “include” and “comprise,” aswell as derivatives thereof, mean inclusion without limitation; the term“or,” is inclusive, meaning and/or; the phrases “associated with” and“associated therewith,” as well as derivatives thereof, may mean toinclude, be included within, interconnect with, contain, be containedwithin, connect to or with, couple to or with, be communicable with,cooperate with, interleave, juxtapose, be proximate to, be bound to orwith, have, have a property of, or the like; and the term “controller”means any device, system or part thereof that controls at least oneoperation, such a device may be implemented in hardware, firmware orsoftware, or some combination of at least two of the same. It should benoted that the functionality associated with any particular controllermay be centralized or distributed, whether locally or remotely.

Moreover, various functions described below can be implemented orsupported by one or more computer programs, each of which is formed fromcomputer readable program code and embodied in a computer readablemedium. The terms “application” and “program” refer to one or morecomputer programs, software components, sets of instructions,procedures, functions, objects, classes, instances, related data, or aportion thereof adapted for implementation in a suitable computerreadable program code. The phrase “computer readable program code”includes any type of computer code, including source code, object code,and executable code. The phrase “computer readable medium” includes anytype of medium capable of being accessed by a computer, such as readonly memory (ROM), random access memory (RAM), a hard disk drive, acompact disc (CD), a digital video disc (DVD), or any other type ofmemory. A “non-transitory” computer readable medium excludes wired,wireless, optical, or other communication links that transporttransitory electrical or other signals. A non-transitory computerreadable medium includes media where data can be permanently stored andmedia where data can be stored and later overwritten, such as arewritable optical disc or an erasable memory device.

Definitions for certain words and phrases are provided throughout thispatent document, those of ordinary skill in the art should understandthat in many, if not most instances, such definitions apply to prior, aswell as future uses of such defined words and phrases.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features, and advantages of certainembodiments of the disclosure will be more apparent from the followingdescription taken in conjunction with the accompanying drawings, inwhich:

FIG. 1 shows the operation for explaining an example of early datatransmission (EDT).

FIG. 2 shows the operation for explaining another example of EDT.

FIG. 3 illustrates NG-RAN architecture supporting PC5 interface.

FIG. 4 illustrates an embodiment of UE operation when scheduling mode ischanged from M2 to M1 for one or more SL LCHs.

FIG. 5 illustrates another embodiment of UE operation when schedulingmode is changed from M2 to M1 for one or more SL LCHs.

FIG. 6 illustrates another embodiment of UE operation when schedulingmode is changed from M2 to M1 for one or more SL LCHs.

FIG. 7 illustrates another embodiment of UE operation when schedulingmode is changed from M2 to M1 for one or more SL LCHs.

FIG. 8 illustrates an embodiment of UE operation when scheduling mode ischanged from M1 to M2 for one or more SL LCHs.

FIG. 9 illustrates another embodiment of UE operation when schedulingmode is changed from M1 to M2 for one or more SL LCHs.

FIG. 10 is a block diagram of a UE according to an embodiment of thedisclosure.

FIG. 11 is a block diagram of a base station according to an embodimentof the disclosure.

FIGS. 12-15 each illustrate example SL LCHs associated with adestination or source and destination pair according to embodiments ofthe disclosure.

FIGS. 16-25 each illustrate examples of preambles according toembodiments of the disclosure.

FIG. 26 is a block diagram of a terminal according to an embodiment ofthe disclosure.

FIG. 27 is a block diagram of a base station according to an embodimentof the disclosure.

Throughout the drawings, like reference numerals will be understood torefer to like parts, components, and structures.

DETAILED DESCRIPTION

FIGS. 1 through 11, discussed below, and the various embodiments used todescribe the principles of the present disclosure in this patentdocument are by way of illustration only and should not be construed inany way to limit the scope of the disclosure. Those skilled in the artwill understand that the principles of the present disclosure may beimplemented in any suitably arranged system or device.

The following description with reference to the accompanying drawings isprovided to assist in a comprehensive understanding of variousembodiments of the disclosure as defined by the claims and theirequivalents. It includes various specific details to assist in thatunderstanding but these are to be regarded as merely exemplary.Accordingly, those of ordinary skill in the art will recognize thatvarious changes and modifications of the various embodiments describedherein can be made without departing from the scope and spirit of thedisclosure. In addition, descriptions of well-known functions andconstructions may be omitted for clarity and conciseness.

The terms and words used in the following description and claims are notlimited to the bibliographical meanings, but are merely used by theinventor to enable a clear and consistent understanding of thedisclosure. Accordingly, it should be apparent to those skilled in theart that the following description of various embodiments of thedisclosure is provided for illustration purpose only and not for thepurpose of limiting the disclosure as defined by the appended claims andtheir equivalents.

It is to be understood that the singular forms “a,” “an,” and “the”include plural referents unless the context clearly dictates otherwise.Thus, for example, reference to “a component surface” includes referenceto one or more of such surfaces.

By the term “substantially” it is meant that the recited characteristic,parameter, or value need not be achieved exactly, but that deviations orvariations, including for example, tolerances, measurement error,measurement accuracy limitations and other factors known to those ofskill in the art, may occur in amounts that do not preclude the effectthe characteristic was intended to provide.

It is known to those skilled in the art that blocks of a flowchart (orsequence diagram) and a combination of flowcharts may be represented andexecuted by computer program instructions. These computer programinstructions may be loaded on a processor of a general purpose computer,special purpose computer, or programmable data processing equipment.When the loaded program instructions are executed by the processor, theycreate a means for carrying out functions described in the flowchart.Because the computer program instructions may be stored in a computerreadable memory that is usable in a specialized computer or aprogrammable data processing equipment, it is also possible to createarticles of manufacture that carry out functions described in theflowchart. Because the computer program instructions may be loaded on acomputer or a programmable data processing equipment, when executed asprocesses, they may carry out operations of functions described in theflowchart.

A block of a flowchart may correspond to a module, a segment, or a codecontaining one or more executable instructions implementing one or morelogical functions, or may correspond to a part thereof. In some cases,functions described by blocks may be executed in an order different fromthe listed order. For example, two blocks listed in sequence may beexecuted at the same time or executed in reverse order.

In this description, the words “unit”, “module” or the like may refer toa software component or hardware component, such as, for example, afield-programmable gate array (FPGA) or an application-specificintegrated circuit (ASIC) capable of carrying out a function or anoperation. However, a “unit”, or the like, is not limited to hardware orsoftware. A unit, or the like, may be configured so as to reside in anaddressable storage medium or to drive one or more processors. Units, orthe like, may refer to software components, object-oriented softwarecomponents, class components, task components, processes, functions,attributes, procedures, subroutines, program code segments, drivers,firmware, microcode, circuits, data, databases, data structures, tables,arrays or variables. A function provided by a component and unit may bea combination of smaller components and units, and may be combined withothers to compose larger components and units. Components and units maybe configured to drive a device or one or more processors in a securemultimedia card.

Prior to the detailed description, terms or definitions necessary tounderstand the disclosure are described. However, these terms should beconstrued in a non-limiting way.

The “base station (B S)” is an entity communicating with a userequipment (UE) and may be referred to as BS, base transceiver station(BTS), node B (NB), evolved NB (eNB), access point (AP), fifthgeneration (5G) NB (5gNB), or next generation NB (gNB).

The “UE” is an entity communicating with a BS and may be referred to asUE, device, mobile station (MS), mobile equipment (ME), or terminal.

In the recent years several broadband wireless technologies have beendeveloped to meet the growing number of broadband subscribers and toprovide more and better applications and services. The second generationwireless communication system has been developed to provide voiceservices while ensuring the mobility of users. Third generation wirelesscommunication system supports not only the voice service but also dataservice. In recent years, the fourth wireless communication system hasbeen developed to provide high-speed data service. However, currently,the fourth generation wireless communication system suffers from lack ofresources to meet the growing demand for high speed data services. So,fifth generation wireless communication system (also referred as nextgeneration radio or NR) is being developed to meet the growing demandfor high speed data services, support ultra-reliability and low latencyapplications.

The fifth generation wireless communication system supports not onlylower frequency bands but also in higher frequency (mmWave) bands, e.g.,10 GHz to 100 GHz bands, so as to accomplish higher data rates. Tomitigate propagation loss of the radio waves and increase thetransmission distance, the beamforming, massive Multiple-InputMultiple-Output (MIMO), Full Dimensional MIMO (FD-MIMO), array antenna,an analog beam forming, large scale antenna techniques are beingconsidered in the design of fifth generation wireless communicationsystem. In addition, the fifth generation wireless communication systemis expected to address different use cases having quite differentrequirements in terms of data rate, latency, reliability, mobility etc.However, it is expected that the design of the air-interface of thefifth generation wireless communication system would be flexible enoughto serve the UEs having quite different capabilities depending on theuse case and market segment the UE cater service to the end customer.For example, use cases for the fifth generation wireless communicationsystem wireless system are expected to address is enhanced MobileBroadband (eMBB), massive Machine Type Communication (m-MTC),ultra-reliable low latency communication (URLL) etc. The eMBBrequirements like tens of Gbps data rate, low latency, high mobility soon and so forth address the market segment representing the conventionalwireless broadband subscribers needing internet connectivity everywhere,all the time and on the go. The m-MTC requirements like very highconnection density, infrequent data transmission, very long batterylife, low mobility address so on and so forth address the market segmentrepresenting the Internet of Things (IoT)/Internet of Everything (IoE)envisioning connectivity of billions of devices. The URLL requirementslike very low latency, very high reliability and variable mobility so onand so forth address the market segment representing the Industrialautomation application, vehicle-to-vehicle/vehicle-to-infrastructurecommunication foreseen as one of the enablers for autonomous cars.

In the fifth generation wireless communication system operating inhigher frequency (mmWave) bands, UE and gNB communicates with each otherusing Beamforming. Beamforming techniques are used to mitigate thepropagation path losses and to increase the propagation distance forcommunication at higher frequency band. Beamforming enhances thetransmission and reception performance using a high-gain antenna.Beamforming can be classified into Transmission (TX) beamformingperformed in a transmitting end and reception (RX) beamforming performedin a receiving end. In general, the TX beamforming increases directivityby allowing an area in which propagation reaches to be densely locatedin a specific direction by using a plurality of antennas. In thissituation, aggregation of the plurality of antennas can be referred toas an antenna array, and each antenna included in the array can bereferred to as an array element. The antenna array can be configured invarious forms such as a linear array, a planar array, etc. The use ofthe TX beamforming results in the increase in the directivity of asignal, thereby increasing a propagation distance. Further, since thesignal is almost not transmitted in a direction other than a directivitydirection, a signal interference acting on another receiving end issignificantly decreased. The receiving end can perform beamforming on aRX signal by using a RX antenna array. The RX beamforming increases theRX signal strength transmitted in a specific direction by allowingpropagation to be concentrated in a specific direction, and excludes asignal transmitted in a direction other than the specific direction fromthe RX signal, thereby providing an effect of blocking an interferencesignal. By using beamforming technique, a transmitter can make pluralityof transmit beam patterns of different directions. Each of thesetransmit beam patterns can be also referred as transmit (TX) beam.Wireless communication system operating at high frequency uses pluralityof narrow TX beams to transmit signals in the cell as each narrow TXbeam provides coverage to a part of cell. The narrower the TX beam,higher is the antenna gain and hence the larger the propagation distanceof signal transmitted using beamforming. A receiver can also makeplurality of receive (RX) beam patterns of different directions. Each ofthese receive patterns can be also referred as receive (RX) beam.

The fifth generation wireless communication system supports standalonemode of operation as well dual connectivity (DC). In DC a multiple Rx/TxUE may be configured to utilize resources provided by two differentnodes (or NBs) connected via non-ideal backhaul. One node acts as theMaster Node (MN) and the other as the Secondary Node (SN). The MN and SNare connected via a network interface and at least the MN is connectedto the core network. NR also supports Multi-RAT Dual Connectivity(MR-DC) operation whereby a UE in RRC_CONNECTED is configured to utilizeradio resources provided by two distinct schedulers, located in twodifferent nodes connected via a non-ideal backhaul and providing eitherE-UTRA (i.e., if the node is an ng-eNB) or NR access (i.e., if the nodeis a gNB). In NR for a UE in RRC_CONNECTED not configured with CA/DCthere is only one serving cell comprising of the primary cell. For a UEin RRC_CONNECTED configured with CA/DC the term ‘serving cells’ is usedto denote the set of cells comprising of the Special Cell(s) and allsecondary cells. In NR the term Master Cell Group (MCG) refers to agroup of serving cells associated with the Master Node, comprising ofthe PCell and optionally one or more SCells. In NR the term SecondaryCell Group (SCG) refers to a group of serving cells associated with theSecondary Node, comprising of the PSCell and optionally one or moreSCells. In NR PCell (primary cell) refers to a serving cell in MCG,operating on the primary frequency, in which the UE either performs theinitial connection establishment procedure or initiates the connectionre-establishment procedure. In NR for a UE configured with CA, Scell isa cell providing additional radio resources on top of Special Cell.Primary SCG Cell (PSCell) refers to a serving cell in SCG in which theUE performs random access when performing the Reconfiguration with Syncprocedure. For Dual Connectivity operation the term SpCell (i.e.,Special Cell) refers to the PCell of the MCG or the PSCell of the SCG,otherwise the term Special Cell refers to the PCell.

In the fifth generation wireless communication system, Physical DownlinkControl Channel (PDCCH) is used to schedule DL transmissions on PDSCHand UL transmissions on PUSCH, where the Downlink Control Information(DCI) on PDCCH includes: Downlink assignments containing at leastmodulation and coding format, resource allocation, and hybrid-ARQinformation related to DL-SCH; Uplink scheduling grants containing atleast modulation and coding format, resource allocation, and hybrid-ARQinformation related to UL-SCH. In addition to scheduling, PDCCH can beused to for: Activation and deactivation of configured PUSCHtransmission with configured grant; Activation and deactivation of PDSCHsemi-persistent transmission; Notifying one or more UEs of the slotformat; Notifying one or more UEs of the PRB(s) and OFDM symbol(s) wherethe UE may assume no transmission is intended for the UE; Transmissionof TPC commands for PUCCH and PUSCH; Transmission of one or more TPCcommands for SRS transmissions by one or more UEs; Switching a UE'sactive bandwidth part; Initiating a random access procedure. A UEmonitors a set of PDCCH candidates in the configured monitoringoccasions in one or more configured COntrol REsource SETs (CORESETs)according to the corresponding search space configurations. A CORESETconsists of a set of PRBs with a time duration of 1 to 3 OFDM symbols.The resource units Resource Element Groups (REGs) and Control ChannelElements (CCEs) are defined within a CORESET with each CCE consisting aset of REGs. Control channels are formed by aggregation of CCE.Different code rates for the control channels are realized byaggregating different number of CCE. Interleaved and non-interleavedCCE-to-REG mapping are supported in a CORESET. Polar coding is used forPDCCH. Each resource element group carrying PDCCH carries its own DMRS.QPSK modulation is used for PDCCH.

In fifth generation wireless communication system, a list of searchspace configurations is signaled by gNB for each configured BWP whereineach search configuration is uniquely identified by an identifier.Identifier of search space configuration to be used for specific purposesuch as paging reception, SI reception, random access response receptionis explicitly signaled by gNB. In NR search space configurationcomprises of parameters Monitoring-periodicity-PDCCH-slot,Monitoring-offset-PDCCH-slot, Monitoring-symbol s-PDCCH-within-slot andduration. A UE determines PDCCH monitoring occasion (s) within a slotusing the parameters PDCCH monitoring periodicity(Monitoring-periodicity-PDCCH-slot), the PDCCH monitoring offset(Monitoring-offset-PDCCH-slot), and the PDCCH monitoring pattern(Monitoring-symbols-PDCCH-within-slot). PDCCH monitoring occasions arethere in slots ‘x’ to x+duration where the slot with number ‘x’ in aradio frame with number ‘y’ satisfies the equation below:(y*(number of slots in a radioframe)+x−Monitoring-offset-PDCCH-slot)mod(Monitoring-periodicity-PDCCH-slot)=0;

The starting symbol of a PDCCH monitoring occasion in each slot havingPDCCH monitoring occasion is given byMonitoring-symbols-PDCCH-within-slot. The length (in symbols) of a PDCCHmonitoring occasion is given in the corset associated with the searchspace. Search space configuration includes the identifier of CORESETconfiguration associated with it. A list of CORESET configurations issignaled by gNB for each configured BWP wherein each CORESETconfiguration is uniquely identified by an identifier. Note that eachradio frame is of 10 ms duration. Radio frame is identified by a radioframe number or system frame number. Each radio frame comprises ofseveral slots wherein the number of slots in a radio frame and durationof slots depends on sub carrier spacing. The number of slots in a radioframe and duration of slots depends radio frame for each supported SCSis pre-defined in NR. Each CORESET configuration is associated with alist of TCI (transmission configuration indicator) states. One DL RS ID(SSB or CSI RS) is configured per TCI state. The list of TCI statescorresponding to a CORESET configuration is signaled by gNB via RRCsignaling. One of the TCI state in TCI state list is activated andindicated to UE by gNB. TCI state indicates the DL TX beam (DL TX beamis QCLed with SSB/CSI RS of TCI state) used by gNB for transmission ofPDCCH in the PDCCH monitoring occasions of a search space.

In fifth generation wireless communication system bandwidth adaptation(BA) is supported. With BA, the receive and transmit bandwidth of a UEneed not be as large as the bandwidth of the cell and can be adjusted:the width can be ordered to change (e.g., to shrink during period of lowactivity to save power); the location can move in the frequency domain(e.g., to increase scheduling flexibility); and the subcarrier spacingcan be ordered to change (e.g., to allow different services). A subsetof the total cell bandwidth of a cell is referred to as a Bandwidth Part(BWP). BA is achieved by configuring RRC connected UE with BWP(s) andtelling the UE which of the configured BWPs is currently the active one.When BA is configured, the UE only has to monitor PDCCH on the oneactive BWP i.e., it does not have to monitor PDCCH on the entire DLfrequency of the serving cell. In RRC connected state, UE is configuredwith one or more DL and UL BWPs, for each configured Serving Cell (i.e.,PCell or SCell). For an activated Serving Cell, there is always oneactive UL and DL BWP at any point in time. The BWP switching for aServing Cell is used to activate an inactive BWP and deactivate anactive BWP at a time. The BWP switching is controlled by the PDCCHindicating a downlink assignment or an uplink grant, by thebwp-InactivityTimer, by RRC signaling, or by the MAC entity itself uponinitiation of Random Access procedure. Upon addition of SpCell oractivation of an SCell, the DL BWP and UL BWP indicated byfirstActiveDownlinkBWP-Id and firstActiveUplinkBWP-Id respectively isactive without receiving PDCCH indicating a downlink assignment or anuplink grant. The active BWP for a Serving Cell is indicated by eitherRRC or PDCCH. For unpaired spectrum, a DL BWP is paired with a UL BWP,and BWP switching is common for both UL and DL. Upon expiry of BWPinactivity timer UE switch to the active DL BWP to the default DL BWP orinitial DL BWP (if default DL BWP is not configured).

In the 5G wireless communication system, random access (RA) issupported. Random access (RA) is used to achieve uplink (UL) timesynchronization. RA is used during initial access, handover, radioresource control (RRC) connection re-establishment procedure, schedulingrequest transmission, secondary cell group (SCG) addition/modification,beam failure recovery and data or control information transmission in ULby non-synchronized UE in RRC CONNECTED state. Several types of randomaccess procedure are supported.

Contention Based Random Access (CBRA)

This is also referred as 4 step CBRA. In this type of random access, UEfirst transmits Random Access preamble (also referred as Msg1) and thenwaits for Random access response (RAR) in the RAR window. RAR is alsoreferred as Msg2. Next generation node B (gNB) transmits the RAR onphysical downlink shared channel (PDSCH). PDCCH scheduling the PDSCHcarrying RAR is addressed to RA-radio network temporary identifier(RA-RNTI). RA-RNTI identifies the time-frequency resource (also referredas physical RA channel (PRACH) occasion or PRACH transmission (TX)occasion or RA channel (RACH) occasion) in which RA preamble wasdetected by gNB. The RA-RNTI is calculated as follows:RA-RNTI=1+s_id+14*t_id+14*80*f_id+14*80*8*ul_carrier_id, where s_id isthe index of the first orthogonal frequency division multiplexing (OFDM)symbol of the PRACH occasion where UE has transmitted Msg1, i.e. RApreamble; 0≤s_id<14; t_id is the index of the first slot of the PRACHoccasion (0≤t_id<80); f_id is the index of the PRACH occasion within theslot in the frequency domain (0≤f_id<8), and ul_carrier_id is the ULcarrier used for Msg1 transmission (0 for normal UL (NUL) carrier and 1for supplementary UL (SUL) carrier. Several RARs for various Randomaccess preambles detected by gNB can be multiplexed in the same RARmedia access control (MAC) protocol data unit (PDU) by gNB. An RAR inMAC PDU corresponds to UE's RA preamble transmission if the RAR includesan RA preamble identifier (RAPID) of RA preamble transmitted by the UE.If the RAR corresponding to its RA preamble transmission is not receivedduring the RAR window and UE has not yet transmitted the RA preamble fora configurable (configured by gNB in RACH configuration) number oftimes, the UE goes back to first step i.e., select random accessresource (preamble/RACH occasion) and transmits the RA preamble. Abackoff may be applied before going back to first step.

If the RAR corresponding to its RA preamble transmission is received theUE transmits message 3 (Msg3) in UL grant received in RAR. Msg3 includesmessage such as RRC connection request, RRC connection re-establishmentrequest, RRC handover confirm, scheduling request, SI request etc. Itmay include the UE identity (i.e., cell-radio network temporaryidentifier (C-RNTI) or system architecture evolution (SAE)-temporarymobile subscriber identity (S-TMSI) or a random number). Aftertransmitting the Msg3, UE starts a contention resolution timer. Whilethe contention resolution timer is running, if UE receives a physicaldownlink control channel (PDCCH) addressed to C-RNTI included in Msg3,contention resolution is considered successful, contention resolutiontimer is stopped and RA procedure is completed. While the contentionresolution timer is running, if UE receives contention resolution MACcontrol element (CE) including the UE's contention resolution identity(first X bits of common control channel (CCCH) service data unit (SDU)transmitted in Msg3), contention resolution is considered successful,contention resolution timer is stopped and RA procedure is completed. Ifthe contention resolution timer expires and UE has not yet transmittedthe RA preamble for a configurable number of times, UE goes back tofirst step i.e., select random access resource (preamble/RACH occasion)and transmits the RA preamble. A backoff may be applied before goingback to first step.

PRACH occasions (or ROs) for 4 step PRACH preamble transmission areindicated by parameter prach-ConfigIndex. SS/PBCH blocks (SSBs) aremapped to valid PRACH occasions in the following order:

-   -   First, in increasing order of preamble indexes within a single        PRACH occasion    -   Second, in increasing order of frequency resource indexes for        frequency multiplexed PRACH occasions    -   Third, in increasing order of time resource indexes for time        multiplexed PRACH occasions within a PRACH slot    -   Fourth, in increasing order of indexes for PRACH slots

For paired spectrum or supplementary uplink band all PRACH occasions arevalid.

For unpaired spectrum,

-   -   if a UE is not provided tdd-UL-DL-ConfigurationCommon, a PRACH        occasion in a PRACH slot is valid if it does not precede a        SS/PBCH block in the PRACH slot and starts at least N_(gap)        symbols after a last SS/PBCH block reception symbol, where        N_(gap) is provided in Table 8.1-2.    -   If a UE is provided tdd-UL-DL-ConfigurationCommon, a PRACH        occasion in a PRACH slot is valid if    -   it is within UL symbols, or    -   it does not precede a SS/PBCH block in the PRACH slot and starts        at least N_(gap) symbols after a last downlink symbol and at        least N_(gap) symbols after a last SS/PBCH block symbol, where        N_(gap) is 0 for preamble SCS of 1.25 KHz and 5 KHz, N_(gap) is        2 for preamble SCS of 15 KHz, 30 KHz, 60 KHz and 120 KHz.

An association period, starting from frame 0, for mapping SS/PBCH blocksto SSB PRACH occasions is the period such that N_(Tx) ^(SSB) SS/PBCHblocks are mapped at least once to the PRACH occasions within theassociation period, where a UE obtains N_(Tx) ^(SSB) from the value ofssb-PositionsInBurst in SIB1 or in ServingCellConfigCommon. Anassociation pattern period includes one or more association periods andis determined so that a pattern between PRACH occasions and SS/PBCHblocks repeats at most every 160 msec.

For 4 step CBRA, if N<1, one SS/PBCH block is mapped to 1/N consecutivevalid PRACH occasions and R contention based preambles with consecutiveindexes associated with the SS/PBCH block per valid PRACH occasion startfrom zero, where N is number of SSBs per PRACH occasion and R is numberof contention based preambles per SSB for 4 step CBRA. If N≥1, Rcontention based preambles with consecutive indexes associated withSS/PBCH block n, 0≤n≤N−1, per valid PRACH occasion start from preambleindex n·N_(preamble) ^(total)/N where N_(preamble) ^(total) preamble isprovided by totalNumberOfRA-Preambles, and is an integer multiple of N.

Contention Free Random Access (CFRA)

This is also referred as legacy CFRA or 4 step CFRA. CFRA procedure isused for scenarios such as handover where low latency is required,timing advance establishment for secondary cell (Scell), etc. Evolvednode B (eNB) assigns to UE dedicated Random access preamble. UEtransmits the dedicated RA preamble. ENB transmits the RAR on PDSCHaddressed to RA-RNTI. RAR conveys RA preamble identifier and timingalignment information. RAR may also include UL grant. RAR is transmittedin RAR window similar to contention based RA (CBRA) procedure. CFRA isconsidered successfully completed after receiving the RAR including RApreamble identifier (RAPID) of RA preamble transmitted by the UE. Incase RA is initiated for beam failure recovery, CFRA is consideredsuccessfully completed if PDCCH addressed to C-RNTI is received insearch space for beam failure recovery. If the RAR window expires and RAis not successfully completed and UE has not yet transmitted the RApreamble for a configurable (configured by gNB in RACH configuration)number of times, the UE retransmits the RA preamble.

For certain events such has handover and beam failure recovery ifdedicated preamble(s) are assigned to UE, during first step of randomaccess i.e., during random access resource selection for Msg1transmission UE determines whether to transmit dedicated preamble or nondedicated preamble. Dedicated preambles are typically provided for asubset of SSBs/CSI RSs. If there is no SSB/CSI RS having DL RSRP above athreshold amongst the SSBs/CSI RSs for which contention free randomaccess resources (i.e., dedicated preambles/ROs) are provided by gNB, UEselect non dedicated preamble. Otherwise, UE select dedicated preamble.So, during the RA procedure, one random access attempt can be CFRA whileother random access attempt can be CBRA.

2 Step Contention Based Random Access (2 Step CBRA)

In the first step, UE transmits random access preamble on PRACH and apayload (i.e., MAC PDU) on PUSCH. The random access preamble and payloadtransmission is also referred as MsgA. In the second step, after MsgAtransmission, the UE monitors for a response from the network (i.e.,gNB) within a configured window. The response is also referred as MsgB.If CCCH SDU was transmitted in MsgA payload, UE performs contentionresolution using the contention resolution information in MsgB. Thecontention resolution is successful if the contention resolutionidentity received in MsgB matches first 48 bits of CCCH SDU transmittedin MsgA. If C-RNTI was transmitted in MsgA payload, the contentionresolution is successful if UE receives PDCCH addressed to C-RNTI. Ifcontention resolution is successful, random access procedure isconsidered successfully completed. Instead of contention resolutioninformation corresponding to the transmitted MsgA, MsgB may include afallback information corresponding to the random access preambletransmitted in MsgA. If the fallback information is received, UEtransmits Msg3 and performs contention resolution using Msg4 as in CBRAprocedure. If contention resolution is successful, random accessprocedure is considered successfully completed. If contention resolutionfails upon fallback (i.e., upon transmitting Msg3), UE retransmits MsgA.If configured window in which UE monitor network response aftertransmitting MsgA expires and UE has not received MsgB includingcontention resolution information or fallback information as explainedabove, UE retransmits MsgA. If the random access procedure is notsuccessfully completed even after transmitting the msgA configurablenumber of times, UE fallbacks to 4 step RACH procedure i.e., UE onlytransmits the PRACH preamble.

MsgA payload may include one or more of common control channel (CCCH)service data unit (SDU), dedicated control channel (DCCH) SDU, dedicatedtraffic channel (DTCH) SDU, buffer status report (BSR) MAC controlelement (CE), power headroom report (PHR) MAC CE, SSB information,C-RNTI MAC CE, or padding. MsgA may include UE ID (e.g., random ID,S-TMSI, C-RNTI, resume ID, etc.) along with preamble in first step. TheUE ID may be included in the MAC PDU of the MsgA. UE ID such as C-RNTImay be carried in MAC CE wherein MAC CE is included in MAC PDU. Other UEIDs (such random ID, S-TMSI, C-RNTI, resume ID, etc.) may be carried inCCCH SDU. The UE ID can be one of random ID, S-TMSI, C-RNTI, resume ID,IMSI, idle mode ID, inactive mode ID, etc. The UE ID can be different indifferent scenarios in which UE performs the RA procedure. When UEperforms RA after power on (before it is attached to the network), thenUE ID is the random ID. When UE perform RA in IDLE state after it isattached to network, the UE ID is S-TMSI. If UE has an assigned C-RNTI(e.g., in connected state), the UE ID is C-RNTI. In case UE is inINACTIVE state, UE ID is resume ID. In addition to UE ID, some additionctrl information can be sent in MsgA. The control information may beincluded in the MAC PDU of the MsgA. The control information may includeone or more of connection request indication, connection resume requestindication, SI request indication, buffer status indication, beaminformation (e.g., one or more DL TX beam ID(s) or SSB ID(s)), beamfailure recovery indication/information, data indicator, cell/BS/TRPswitching indication, connection re-establishment indication,reconfiguration complete or handover complete message, etc.

For 2 step CBRA, SS/PBCH blocks (SSBs) are mapped to valid PRACHoccasions in same manner as 4 step CBRA.

2 Step Contention Free Random Access (2 Step CFRA)

In this case gNB assigns to UE dedicated Random access preamble (s) andPUSCH resource(s) for MsgA transmission. RO(s) to be used for preambletransmission may also be indicated. In the first step, UE transmitsrandom access preamble on PRACH and a payload on PUSCH using thecontention free random access resources (i.e., dedicated preamble/PUSCHresource/RO). In the second step, after MsgA transmission, the UEmonitors for a response from the network (i.e., gNB) within a configuredwindow. If UE receives PDCCH addressed to C-RNTI, random accessprocedure is considered successfully completed. If UE receives fallbackinformation corresponding to its transmitted preamble, random accessprocedure is considered successfully completed.

For certain events such has handover and beam failure recovery ifdedicated preamble(s) and PUSCH resource(s) are assigned to UE, duringfirst step of random access i.e., during random access resourceselection for MsgA transmission UE determines whether to transmitdedicated preamble or non dedicated preamble. Dedicated preambles aretypically provided for a subset of SSBs/CSI RSs. If there is no SSB/CSIRS having DL RSRP above a threshold amongst the SSBs/CSI RSs for whichcontention free random access resources (i.e., dedicatedpreambles/ROs/PUSCH resources) are provided by gNB, UE select nondedicated preamble. Otherwise, UE select dedicated preamble. So, duringthe RA procedure, one random access attempt can be 2 step CFRA whileother random access attempt can be 2 step CBRA.

Upon initiation of random access procedure, UE first selects the carrier(SUL or NUL). If the carrier to use for the Random Access procedure isexplicitly signaled by gNB, UE select the signaled carrier forperforming Random Access procedure. If the carrier to use for the RandomAccess procedure is not explicitly signaled by gNB; and if the ServingCell for the Random Access procedure is configured with supplementaryuplink and if the RSRP of the downlink pathloss reference is less thanrsrp-ThresholdSSB-SUL: UE select the SUL carrier for performing RandomAccess procedure. Otherwise, UE select the NUL carrier for performingRandom Access procedure. Upon selecting the UL carrier, UE determinesthe UL and DL BWP for random access procedure as specified in section5.15 of TS 38.321. UE then determines whether to perform 2 step or 4step RACH for this random access procedure.

-   -   If this random access procedure is initiated by PDCCH order and        if the ra-PreambleIndex explicitly provided by PDCCH is not        0b000000, UE selects 4 step RACH.    -   else if 2 step contention free random access resources are        signaled by gNB for this random access procedure, UE selects 2        step RACH.    -   else if 4 step contention free random access resources are        signaled by gNB for this random access procedure, UE selects 4        step RACH.    -   else if the UL BWP selected for this random access procedure is        configured with only 2 step RACH resources, UE selects 2 step        RACH.    -   else if the UL BWP selected for this random access procedure is        configured with only 4 step RACH resources, UE selects 4 step        RACH.    -   else if the UL BWP selected for this random access procedure is        configured with both 2 step and 4 step RACH resources,    -   if RSRP of the downlink pathloss reference is below a configured        threshold, UE selects 4 step RACH. Otherwise, UE selects 2 step        RACH.

In the fifth generation wireless communication system, node B (gNB) orbase station in cell broadcast Synchronization Signal and PBCH block(SSB) consists of primary and secondary synchronization signals (PSS,SSS) and system information. System information includes commonparameters needed to communicate in cell. In the fifth generationwireless communication system (also referred as next generation radio orNR), System Information (SI) is divided into the MIB and a number ofSIBs where:

-   -   the MIB is always transmitted on the BCH with a periodicity of        80 milliseconds (ms) and repetitions made within 80 ms and it        includes parameters that are needed to acquire SIB1 from the        cell.    -   the SIB1 is transmitted on the DL-SCH with a periodicity of 160        ms and variable transmission repetition. The default        transmission repetition periodicity of SIB1 is 20 ms but the        actual transmission repetition periodicity is up to network        implementation. The scheduling information in SIB 1 includes        mapping between SIBs and SI messages, periodicity of each SI        message and SI window length. The scheduling information in SIB        1 includes an indicator for each SI message, which indicates        whether the concerned SI message is being broadcasted or not. If        at least one SI message is not being broadcasted, SIB1 may        include random access resources (PRACH preamble(s) and PRACH        resource(s)) for requesting gNB to broadcast one or more SI        message(s).    -   SIBs other than SIB1 are carried in SystemInformation (SI)        messages, which are transmitted on the DL-SCH. Only SIBs having        the same periodicity can be mapped to the same SI message. Each        SI message is transmitted within periodically occurring time        domain windows (referred to as SI-windows with same length for        all SI messages). Each SI message is associated with a SI-window        and the SI-windows of different SI messages do not overlap. That        is, within one SI-window only the corresponding SI message is        transmitted. Any SIB except SIB1 can be configured to be cell        specific or area specific, using an indication in SIB 1. The        cell specific SIB is applicable only within a cell that provides        the SIB while the area specific SIB is applicable within an area        referred to as SI area, which consists of one or several cells        and is identified by systemInformationAreaID.

UE acquires SIB 1 from the camped or serving cell. UE check theBroadcastStatus bit in SIB 1 for SI message which UE needs to acquire.SI request configuration for SUL is signaled by gNB using the IEsi-RequestConfigSUL in SIB1. If the IE si-RequestConfigSUL is notpresent in SIB1, UE considers that SI request configuration for SUL isnot signaled by gNB. SI request configuration for NUL is signaled by gNBusing the IE si-RequestConfig in SIB1. If the IE si-RequestConfig is notpresent in SIB1, UE considers that SI request configuration for NUL isnot signaled by gNB. If SI message which UE needs to acquire is notbeing broadcasted (i.e., BroadcastStatus bit is set to zero), UEinitiates transmission of SI request. The procedure for SI requesttransmission is as follows:

If SI request configuration is signaled by gNB for SUL, and criteria toselect SUL is met (i.e., RSRP derived from SSB measurements of camped orserving cell<rsrp-ThresholdSSB-SUL, where rsrp-ThresholdSSB-SUL issignaled by gNB (e.g., in broadcast signaling such as SIB1)): UEinitiate transmission of SI request based on Msg1 based SI request onSUL. In other words, UE initiates Random Access procedure using thePRACH preamble(s) and PRACH resource(s) in SI request configuration ofSUL. UE transmits Msg1 (i.e., Random access preamble) and waits foracknowledgement for SI request. Random access resources (PRACHpreamble(s) and PRACH occasions(s)) indicated in SI requestconfiguration of SUL is used for Msg1. Msg1 is transmitted on SUL. Ifacknowledgement for SI request is received, UE monitors the SI window ofthe requested SI message in one or more SI period(s) of that SI message.

Else if SI request configuration is signaled by gNB for NUL and criteriato select NUL is met (i.e., NUL is selected if SUL is supported incamped or serving cell and RSRP derived from SSB measurements of campedor serving cell>=rsrp-ThresholdSSB-SUL; OR NUL is selected if SUL is notsupported in serving cell): UE initiate transmission of SI request basedon Msg1 based SI request on NUL (350). In other words, UE initiatesRandom Access procedure using the PRACH preamble(s) and PRACHresource(s) in SI request configuration of NUL. UE transmits Msg1 (i.e.,Random access preamble) and waits for acknowledgement for SI request.Random access resources (PRACH preamble(s) and PRACH occasions(s))indicated in SI request configuration of NUL is used for Msg1. Msg1 istransmitted on NUL. If acknowledgement for SI request is received, UEmonitors the SI window of the requested SI message in one or more SIperiod(s) of that SI message.

Else UE initiate transmission of SI request based on Msg3 based SIrequest. In other words, UE initiate transmission ofRRCSystemInfoRequest message (345). UE transmits Msg1 (i.e., Randomaccess preamble) and waits for random access response. Common randomaccess resources (PRACH preamble(s) and PRACH occasions(s)) are used forMsg1. In the UL grant received in random access response, UE transmitsRRCSystemInfoRequest message and waits for acknowledgement for SIrequest (i.e., RRCSystemInfoRequest message). If acknowledgement for SIrequest (i.e., RRCSystemInfoRequest message) is received, UE monitorsthe SI window of the requested SI message in one or more SI period(s) ofthat SI message. Note that if SUL is configured, UL carrier for Msg1transmission will be selected by UE in similar manner as selected by UEfor Msg1 based SI request. SUL is the selected UL carrier, if RSRPderived from SSB measurements of camped or servingcell<rsrp-ThresholdSSB-SUL where rsrp-ThresholdSSB-SUL is signaled bygNB (e.g., in broadcast signaling such as SIB1). NUL is the selected ULcarrier, if RSRP derived from SSB measurements of camped or servingcell>=rsrp-ThresholdSSB-SUL where rsrp-ThresholdSSB-SUL is signaled bygNB (e.g., in broadcast signaling such as SIB1).

4G wireless communication system supports early data transmission (EDT).EDT allows one uplink data transmission optionally followed by onedownlink data transmission during the random access procedure. EDT istriggered when the upper layers have requested the establishment orresumption of the RRC Connection for Mobile Originated data (i.e., notsignaling or SMS) and the uplink data size is less than or equal to a TBsize indicated in the system information.

In one approach of EDT, uplink user data are transmitted in a NASmessage concatenated in UL RRCEarlyDataRequest message on CCCH. Downlinkuser data are optionally transmitted in a NAS message concatenated in DLRRCEarlyDataComplete message on CCCH. There is no transition to RRCCONNECTED. The detailed procedure (see FIG. 1) is as follows:

Steps 111-113. Upon connection establishment request for MobileOriginated data from the upper layers, the UE (101) initiates the earlydata transmission procedure and selects a random access preambleconfigured for EDT.

Step 115. UE sends RRCEarlyDataRequest message concatenating the userdata on CCCH.

Step 117. The eNB (103) initiates the S1-AP Initial UE message procedureto forward the NAS message and establish the S1 connection. The eNB mayindicate in this procedure that this connection is triggered for EDT.

Step 119. The MME (105) requests the S-GW (107) to re-activate the EPSbearers for the UE.

Step 121. The MME sends the uplink data to the S-GW.

Step 123. If downlink data are available, the S-GW sends the downlinkdata to the MME.

Steps 125 a-125 b. If downlink data are received from the S-GW, the MMEforwards the data to the eNB via DL NAS Transport procedure and may alsoindicate whether further data are expected. Otherwise, the MME maytrigger Connection Establishment Indication procedure and also indicatewhether further data are expected.

Step 127. If no further data are expected, the eNB can send theRRCEarlyDataComplete message on CCCH to keep the UE in RRC_IDLE. Ifdownlink data were received in step 6, they are concatenated inRRCEarlyDataComplete message.

Step 129. The S1 connection is released and the EPS bearers aredeactivated.

NOTE: If the MME or the eNB decides to move the UE in RRC_CONNECTEDmode, RRCConnectionSetup message is sent in step 7 to fall back to thelegacy RRC Connection establishment procedure; the eNB will discard thezero-length NAS PDU received in msg5.

In another approach of EDT, the UE has been provided with aNextHopChainingCount in the RRCConnectionRelease message with suspendindication. Uplink user data are transmitted on DTCH multiplexed with ULRRCConnectionResumeRequest message on CCCH. Downlink user data areoptionally transmitted on DTCH multiplexed with DL RRCConnectionReleasemessage on DCCH. The short resume MAC-I is reused as the authenticationtoken for RRCConnectionResumeRequest message and is calculated using theintegrity key from the previous connection. The user data in uplink anddownlink are ciphered. The keys are derived using theNextHopChainingCount provided in the RRCConnectionRelease message of theprevious RRC connection. The RRCConnectionRelease message is integrityprotected and ciphered using the newly derived keys. There is notransition to RRC CONNECTED. The detailed procedure (see FIG. 2) is asfollows:

Steps 211-213. Upon connection resumption request for Mobile Originateddata from the upper layers, the UE (201) initiates the early datatransmission procedure and selects a random access preamble configuredfor EDT.

Step 215. The UE sends an RRCConnectionResumeRequest to the eNB (203),including its Resume ID, the establishment cause, and an authenticationtoken. The UE resumes all SRBs and DRBs, derives new security keys usingthe NextHopChainingCount provided in the RRCConnectionRelease message ofthe previous connection and re-establishes the AS security. The userdata are ciphered and transmitted on DTCH multiplexed with theRRCConnectionResumeRequest message on CCCH.

Step 217. The eNB initiates the S1-AP Context Resume procedure to resumethe S1 connection and re-activate the S1-U bearers.

Step 219. The MME (205) requests the S-GW (207) to re-activate the S1-Ubearers for the UE.

Step 221. The MME confirms the UE context resumption to the eNB.

Step 223. The uplink data are delivered to the S-GW.

Steps 225. If downlink data are available, the S-GW sends the downlinkdata to the eNB.

Step 227. If no further data are expected from the S-GW, the eNB caninitiate the suspension of the S1 connection and the deactivation of theS1-U bearers.

Step 229. The eNB sends the RRCConnectionRelease message to keep the UEin RRC_IDLE. The message includes the releaseCause set to rrc-Suspend,the resumeID, the NextHopChainingCount and drb-ContinueROHC which arestored by the UE. If downlink data were received in step 6, they aresent ciphered on DTCH multiplexed with the RRCConnectionRelease messageon DCCH.

NOTE: If the MME or eNB decides the UE to move in RRC_CONNECTED mode,RRCConnectionResume message is sent in step 7 to fall back to the RRCConnection resume procedure. In that case, the RRCConnectionResumemessage is integrity protected and ciphered with the keys derived instep 1 and the UE ignores the NextHopChainingCount included in theRRCConnectionResume message. Downlink data can be transmitted on DTCHmultiplexed with the RRCConnectionResume message.

4G and 5G wireless communication system supports vehicular communicationservices. Vehicular communication services, represented by V2X services,can consist of the following four different types: V2V, V2I, V2N andV2P. In fifth generation (also referred as NR or New Radio) wirelesscommunication system, V2X communication is being enhanced to supportenhanced V2X use cases, which are broadly arranged into four use casegroups:

1) Vehicles Platooning enables the vehicles to dynamically form aplatoon travelling together. All the vehicles in the platoon obtaininformation from the leading vehicle to manage this platoon. Theseinformation allow the vehicles to drive closer than normal in acoordinated manner, going to the same direction and travelling together.

2) Extended Sensors enables the exchange of raw or processed datagathered through local sensors or live video images among vehicles, roadsite units, devices of pedestrian and V2X application servers. Thevehicles can increase the perception of their environment beyond of whattheir own sensors can detect and have a more broad and holistic view ofthe local situation. High data rate is one of the key characteristics.

3) Advanced Driving enables semi-automated or full-automated driving.Each vehicle and/or RSU shares its own perception data obtained from itslocal sensors with vehicles in proximity and that allows vehicles tosynchronize and coordinate their trajectories or maneuvers. Each vehicleshares its driving intention with vehicles in proximity too.

4) Remote Driving enables a remote driver or a V2X application tooperate a remote vehicle for those passengers who cannot drive bythemselves or remote vehicles located in dangerous environments. For acase where variation is limited and routes are predictable, such aspublic transportation, driving based on cloud computing can be used.High reliability and low latency are the main requirements.

Referring to FIG. 3, V2X services can be provided by PC5 interfaceand/or Uu interface. Support of V2X services via PC5 interface isprovided by NR sidelink communication or V2X sidelink communication,which is a mode of communication whereby UEs can communicate with eachother directly over the PC5 interface using NR technology or EUTRAtechnology respectively without traversing any network node. Thiscommunication mode is supported when the UE is served by RAN and whenthe UE is outside of RAN coverage. Only the UEs authorized to be usedfor V2X services can perform NR or V2X sidelink communication. TheNG-RAN architecture supports the PC5 interface as illustrated in FIG. 3.Sidelink transmission and reception over the PC5 interface are supportedwhen the UE is inside NG-RAN coverage, irrespective of which RRC statethe UE is in, and when the UE is outside NG-RAN coverage. Support of V2Xservices via the PC5 interface can be provided by NR SidelinkCommunication and/or V2X Sidelink Communication. NR SidelinkCommunication may be used to support other services than V2X services.

NR or V2X Sidelink Communication can support multiple types oftransmission modes. unicast transmission, characterized by support of atleast one PC5-RRC connection between peer UEs; transmission andreception of control information and user traffic between peer UEs insidelink; support of sidelink HARQ feedback; support of RLC AM; andsupport of sidelink RLM for both peer UEs to detect RLF. Groupcasttransmission, characterized by: transmission and reception of usertraffic among UEs belonging to a group in sidelink; support of sidelinkHARQ feedback. Broadcast transmission, characterized by: Transmissionand reception of user traffic among UEs in sidelink.

The AS protocol stack for the control plane in the PC5 interfaceconsists of RRC, PDCP, RLC and MAC sublayer, and the physical layer. TheAS protocol stack for user plane in the PC5 interface consists of SDAP,PDCP, RLC and MAC sublayer, and the physical layer. Sidelink Radiobearers (SLRB) are categorized into two groups: sidelink data radiobearers (SL DRB) for user plane data and sidelink signaling radiobearers (SL SRB) for control plane data. Separate SL SRBs usingdifferent SCCHs are configured for PC5-RRC and PC5-S signalingrespectively.

The MAC sublayer provides the following services and functions over thePC5 interface:

Radio resource selection; Packet filtering; Priority handling betweenuplink and sidelink transmissions for a given UE; Sidelink CSIreporting. With LCP restrictions in MAC, only sidelink logical channelsbelonging to the same destination can be multiplexed into a MAC PDU forevery unicast, groupcast and broadcast transmission which is associatedto the destination. NG-RAN can also control whether a sidelink logicalchannel can utilize the resources allocated to a configured sidelinkgrant Type 1. For packet filtering, a SL-SCH MAC header includingportions of both Source Layer-2 ID and a Destination Layer-2 ID is addedto each MAC PDU as specified in subclause 8.x. LCD included within a MACsubheader uniquely identifies a logical channel within the scope of theSource Layer-2 ID and Destination Layer-2 ID combination. The followinglogical channels are used in sidelink:

-   -   Sidelink Control Channel (SCCH): a sidelink channel for        transmitting control information from one UE to other UE(s);    -   Sidelink Traffic Channel (STCH): a sidelink channel for        transmitting user information from one UE to other UE(s);    -   Sidelink Broadcast Control Channel (SBCCH): a sidelink channel        for broadcasting sidelink system information from one UE to        other UE(s).

The following connections between logical channels and transportchannels exist:

-   -   SCCH can be mapped to SL-SCH;    -   STCH can be mapped to SL-SCH;    -   SBCCH can be mapped to SL-BCH.

The RRC sublayer provides the following services and functions over thePC5 interface:

-   -   Transfer of a PC5-RRC message between peer UEs;    -   Maintenance and release of a PC5-RRC connection between two UEs;    -   Detection of sidelink radio link failure for a PC5-RRC        connection.

A PC5-RRC connection is a logical connection between two UEs for a pairof Source and Destination Layer-2 IDs which is considered to beestablished after a corresponding PC5 unicast link is established asspecified in TS 23.287. There is one-to-one correspondence between thePC5-RRC connection and the PC5 unicast link. A UE may have multiplePC5-RRC connections with one or more UEs for different pairs of Sourceand Destination Layer-2 IDs. Separate PC5-RRC procedures and messagesare used for a UE to transfer UE capability and sidelink configurationincluding SLRB configuration to the peer UE. Both peer UEs can exchangetheir own UE capability and sidelink configuration using separatebi-directional procedures in both sidelink directions. If it is notinterested in sidelink transmission, if sidelink RLF on the PC5-RRCconnection is declared, or if the Layer-2 link release procedure iscompleted as specified in TS 23.287, UE releases the PC5-RRC connection.

The UE can operate in two modes for resource allocation in sidelink:

-   -   Scheduled resource allocation, characterized by:    -   The UE needs to be RRC_CONNECTED in order to transmit data;    -   NG-RAN schedules transmission resources.    -   UE autonomous resource selection, characterized by:    -   The UE can transmit data when inside NG-RAN coverage,        irrespective of which RRC state the UE is in, and when outside        NG-RAN coverage;    -   The UE autonomously selects transmission resources from a pool        of resources.    -   For NR sidelink communication, the UE performs sidelink        transmissions only on a single carrier.

Scheduled Resource Allocation

NG-RAN can dynamically allocate resources to the UE via the SL-RNTI onPDCCH(s) for NR sidelink Communication. In addition, NG-RAN can allocatesidelink resources to UE with two types of configured sidelink grants:

-   -   With type 1, RRC directly provides the configured sidelink grant        for NR sidelink communication    -   With type 2, RRC provides the periodicity of the configured        sidelink grant while PDCCH can either signal and activate the        configured sidelink grant, or deactivate it. The PDCCH provides        the actual grant (i.e., resources) to be used. The PDCCH is        addressed to SL-CS-RNTI for NR sidelink communication and SL        Semi-Persistent Scheduling V-RNTI for V2X sidelink        communication.

For the UE performing NR sidelink communication, there can be more thanone configured sidelink grant activated at a time on the carrierconfigured for sidelink transmission. When beam failure or physicallayer problem occurs on NR Uu, the UE can continue using the configuredsidelink grant Type 1. During handover, the UE can be provided withconfigured sidelink grants via handover command, regardless of the type.If provided, the UE activates the configured sidelink grant Type 1 uponreception of the handover command. The UE can send sidelink bufferstatus report to support scheduler operation in NG-RAN. The sidelinkbuffer status reports refer to the data that is buffered in for a groupof logical channels (LCG) per destination in the UE. Eight LCGs are usedfor reporting of the sidelink buffer status reports. Two formats, whichare SL BSR and truncated SL BSR, are used.

UE sends SL BSR for dynamic resource allocation, in following cases

-   -   SL data, for a sidelink logical channel of a ProSe Destination,        becomes available for transmission in the RLC entity or in the        PDCP entity and either the data belongs to a sidelink logical        channel with higher priority than the priorities of the sidelink        logical channels which belong to any LCG belonging to the same        ProSe Destination and for which data is already available for        transmission, or there is currently no data available for        transmission for any of the sidelink logical channels belonging        to the same ProSe Destination, in which case the Sidelink BSR is        referred below to as “Regular Sidelink BSR”;    -   UL resources are allocated and number of padding bits remaining        after a Padding BSR has been triggered is equal to or larger        than the size of the Sidelink BSR MAC control element containing        the buffer status for at least one LCG of a ProSe Destination        plus its subheader, in which case the Sidelink BSR is referred        below to as “Padding Sidelink BSR”;    -   retx-BSR-TimerSL expires and the MAC entity has data available        for transmission for any of the sidelink logical channels, in        which case the Sidelink BSR is referred below to as “Regular        Sidelink BSR”;    -   periodic-BSR-TimerSL expires, in which case the Sidelink BSR is        referred below to as “Periodic Sidelink BSR”;

UE Autonomous Resource Allocation

The UE autonomously selects sidelink grant from a pool of resourcesprovided by broadcast system information or dedicated signaling whileinside NG-RAN coverage or by preconfiguration while outside NG-RANcoverage.

For NR sidelink communication, the pools of resources can be providedfor a given validity area where the UE does not need to acquire a newpool of resources while moving within the validity area, at least whenthis pool is provided by SIB (e.g., reuse valid area of NR SIB). NR SIBvalidity mechanism is reused to enable validity area for SL resourcepool configured via broadcasted system information. The UE is allowed totemporarily use UE autonomous resource selection with random selectionfor sidelink transmission based on configuration of the exceptionaltransmission resource pool.

For V2X sidelink transmission, during handover, transmission resourcepool configurations including exceptional transmission resource pool forthe target cell can be signaled in the handover command to reduce thetransmission interruption. In this way, the UE may use the V2X sidelinktransmission resource pools of the target cell before the handover iscompleted as long as either synchronization is performed with the targetcell in case eNB is configured as synchronization source orsynchronization is performed with GNSS in case GNSS is configured assynchronization source. If the exceptional transmission resource pool isincluded in the handover command, the UE uses randomly selectedresources from the exceptional transmission resource pool, starting fromthe reception of handover command. If the UE is configured withscheduled resource allocation in the handover command, the UE continuesto use the exceptional transmission resource pool while the timerassociated with handover is running. If the UE is configured withautonomous resource selection in the target cell the UE continues to usethe exceptional transmission resource pool until the sensing results onthe transmission resource pools for autonomous resource selection areavailable. For exceptional cases (e.g., during RLF, during transitionfrom RRC IDLE to RRC CONNECTED or during change of dedicated V2Xsidelink resource pools within a cell), the UE may select resources inthe exceptional pool provided in serving cell's SIB21 or in dedicatedsignaling based on random selection, and uses them temporarily. Duringcell reselection, the RRC_IDLE UE may use the randomly selectedresources from the exceptional transmission resource pool of thereselected cell until the sensing results on the transmission resourcepools for autonomous resource selection are available.

UE can be configured with both scheduled resource allocation (i.e.,Mode 1) and autonomous resource allocation (i.e., Mode 2) schedulingmodes. gNB indicates scheduling mode (Mode 1 or Mode 2) associated witheach SL LCH. UE multiplexes SL LCH(s) associated with same schedulingmode in SL MAC PDU. This approach may lead to wastage of resources. Somemechanism to multiplex SL LCH associated with a scheduling mode in SLgrant of another scheduling mode is needed.

Description of the invention in detail (Including its operation,purpose, environment and how your invention overcomes the shortcomingsof the prior art). Begin with a system level diagram and associated highlevel description of your invention in the context of a possible productdeployment of your invention, for example a handset, a base station,and/or a wireless network comprising one or more base stations and oneor more handsets.

Logical Channel Multiplexing Method 1 Embodiment 1

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation). gNB signals the associated scheduling mode foreach SL LCH (or SL radio bearer). The signaling can be done using RRCsignaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of a destination (or of a source and destination pair) inSL MAC PDU as follows:

-   -   Schedule/include data from SL LCH(s) associated with scheduling        mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   if any resources remain, all the SL LCHs are served in a strict        decreasing priority order (regardless of the value of Bj) until        either the data for that logical channel or the SL grant is        exhausted, whichever comes first. Logical channels configured        with equal priority are served equally (or up to UE        implementation).    -   If all data from SL LCHs associated with scheduling mode of the        SL grant is scheduled/included AND if there is remaining SL        grant: UE schedule/include data from SL LCHs associated with a        scheduling mode different from scheduling mode of the SL grant        as follows:    -   Allocate resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj. Parameter Bj is        maintained for every SL LCH as specified in TS 38.321.    -   if any resources remain, all the SL LCHs having data available        for transmission are served in a strict decreasing priority        order (regardless of the value of Bj) until either the data for        that logical channel or the SL grant is exhausted, whichever        comes first. Logical channels configured with equal priority are        served equally (or up to UE implementation).

FIG. 4 is an example illustration. There are four SL LCHs (LCH A, LCH B,LCH C and LCH D) associated with a destination (or source anddestination pair). LCH A and LCH B are associated with scheduling modeM1. LCH C and LCH D are associated with scheduling mode M2. UE has a SLgrant for scheduling mode M1. UE generates SL MAC PDU using the dataavailable for transmission in SL LCH(s) of a destination (or of a sourceand destination pair) and transmits the generated SL MAC PDU using SLgrant (or SL SCH resources) for M1. In the SL MAC PDU, UE firstschedules data from LCH A and LCH B which are associated with schedulingmode M1 (401). If all data from LCH A and LCH B is scheduled and ifthere is remaining SL grant, UE schedules data from SL LCHs of M2 i.e.,LCH C and LCH D (402).

Embodiment 2

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation). gNB signals the associated scheduling mode foreach SL LCH (or SL radio bearer). The signaling can be done using RRCsignaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of a destination (or of a source and destination pair) inSL MAC PDU as follows:

-   -   Schedule/include data from SL LCH(s) associated with scheduling        mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   if any resources remain, all the SL LCHs having data available        for transmission are served in a strict decreasing priority        order (regardless of the value of Bj) until either the data for        that logical channel or the SL grant is exhausted, whichever        comes first. Logical channels configured with equal priority are        served equally (or up to UE implementation).    -   If ‘multilplexingOtherModeAllowed’ is configured        (multilplexingOtherModeAllowed can be indicated by gNB using RRC        signaling message):    -   if all data from SL LCHs associated with scheduling mode of the        SL grant is scheduled/included AND if there is remaining SL        grant: UE schedule/include data from SL LCHs associated with a        scheduling mode different from scheduling mode of the SL grant        as follows:        -   Allocate resources to SL LCHs with Bj>0 in decreasing            priority, where SL LCHs are allocated resources up to Bj.            Parameter Bj is maintained for every SL LCH as specified in            TS 38.321.    -   if any resources remain, all the SL LCHs having data available        for transmission are served in a strict decreasing priority        order (regardless of the value of Bj) until either the data for        that logical channel or the SL grant is exhausted, whichever        comes first. Logical channels configured with equal priority are        served equally (or up to UE implementation).

Embodiment 3

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation). gNB signals the associated scheduling mode foreach SL LCH (or SL radio bearer). The signaling can be done using RRCsignaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of selected destination (or of a source and destinationpair) in SL MAC PDU as follows:

-   -   schedule/include data from SL LCH(s) associated with scheduling        mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   if any resources remain, all the SL LCHs having data available        for transmission are served in a strict decreasing priority        order (regardless of the value of Bj) until either the data for        that logical channel or the SL grant is exhausted, whichever        comes first. Logical channels configured with equal priority are        served equally (or up to UE implementation).    -   if all data from SL LCHs associated with scheduling mode of the        SL grant is scheduled/included AND if there is remaining SL        grant: UE schedule/include data from SL LCHs associated with a        scheduling mode different from scheduling mode of the SL grant        and for which multilplexingOtherModeAllowed is configured        (multilplexingOtherModeAllowed can be indicated by gNB using RRC        signaling message, indication can be per SL LCH) as follows:    -   Allocate resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj. Parameter Bj is        maintained for every SL LCH as specified in TS 38.321.    -   if any resources remain, all the SL LCHs having data available        for transmission are served in a strict decreasing priority        order (regardless of the value of Bj) until either the data for        that logical channel or the SL grant is exhausted, whichever        comes first. Logical channels configured with equal priority are        served equally (or up to UE implementation).

Method 2 Embodiment 1

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation). gNB signals the associated scheduling mode foreach SL LCH (or SL radio bearer). The signaling can be done using RRCsignaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of a destination (or of a source and destination pair) inSL MAC PDU as follows:

-   -   schedule/include data from SL LCH(s) associated with scheduling        mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   If there is remaining SL grant, allocate resources to the SL        LCHs (irrespective of associated scheduling mode) having data        available for transmission in a strict decreasing priority order        (regardless of the value of Bj) until either the data for that        logical channel or the SL grant is exhausted, whichever comes        first. Logical channels configured with equal priority are        served equally (or up to UE implementation).

FIG. 5 is an example illustration. There are four SL LCHs (LCH A, LCH B,LCH C and LCH D) associated with a destination (or source anddestination pair). LCH A and LCH B are associated with scheduling modeM1. LCH C and LCH D are associated with scheduling mode M2. UE has a SLgrant for scheduling mode M1. UE generates SL MAC PDU using the dataavailable for transmission in SL LCH(s) of a destination (or of a sourceand destination pair) and transmits the generated SL MAC PDU using SLgrant (or SL SCH resources) for M1. In the SL MAC PDU, UE firstschedules data from LCH A and LCH B which are associated with schedulingmode M1, wherein data from LCH A and LCH B is included in decreasingpriority order and up to Bj (501). If there is remaining SL grant, UEschedules data from all SL LCHs (irrespective of scheduling mode) indecreasing priority order (502).

Embodiment 2

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation). gNB signals the associated scheduling mode foreach SL LCH (or SL radio bearer). The signaling can be done using RRCsignaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of a destination (or of a source and destination pair) inSL MAC PDU as follows:

-   -   schedule/include data from SL LCH(s) associated with scheduling        mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   If there is remaining SL grant:    -   If ‘multilplexingOtherModeAllowed’ is configured        (multilplexingOtherModeAllowed can be indicated by gNB using RRC        signaling message):    -   allocate resources to the SL LCHs (irrespective of associated        scheduling mode) having data available for transmission in a        strict decreasing priority order (regardless of the value of Bj)        until either the data for that logical channel or the SL grant        is exhausted, whichever comes first. Logical channels configured        with equal priority are served equally (or up to UE        implementation).    -   Else    -   allocate resources to the SL LCHs associated with scheduling        mode of SL grant having data available for transmission in a        strict decreasing priority order (regardless of the value of Bj)        until either the data for that logical channel or the SL grant        is exhausted, whichever comes first. Logical channels configured        with equal priority are served equally (or up to UE        implementation).

Embodiment 3

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation). gNB signals the associated scheduling mode foreach SL LCH (or SL radio bearer). The signaling can be done using RRCsignaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of a destination (or of a source and destination pair) inSL MAC PDU as follows:

-   -   schedule/include data from SL LCH(s) associated with scheduling        mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   If there is remaining SL grant:    -   allocate resources to the SL LCHs associated with scheduling        mode of SL grant and SL LCHs associated with scheduling mode        different from scheduling mode of SL grant for which        ‘multilplexingOtherModeAllowed’ is configured having data        available for transmission in a strict decreasing priority order        (regardless of the value of Bj) until either the data for that        logical channel or the SL grant is exhausted, whichever comes        first. Logical channels configured with equal priority are        served equally (or up to UE implementation).

Method 3 Embodiment 1

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation). gNB signals the associated scheduling mode foreach SL LCH (or SL radio bearer). The signaling can be done using RRCsignaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of a destination (or of a source and destination pair) inSL MAC PDU as follows:

-   -   Schedule/include data from SL LCH(s) associated with scheduling        mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   If there is remaining SL grant, allocate resources to the SL        LCHs with Bj>0 and associated with scheduling mode different        from scheduling mode of SL grant in a strict decreasing priority        order where SL LCHs are allocated resources up to Bj.    -   If there is still remaining SL grant, allocate resources to the        SL LCHs (irrespective of associated scheduling mode) having data        available for transmission in a strict decreasing priority order        (regardless of the value of Bj) until either the data for that        logical channel or the SL grant is exhausted, whichever comes        first. Logical channels configured with equal priority are        served equally (or up to UE implementation).

FIG. 6 is an example illustration. There are four SL LCHs (LCH A, LCH B,LCH C and LCH D) associated with a destination (or source anddestination pair). LCH A and LCH B are associated with scheduling modeM1. LCH C and LCH D are associated with scheduling mode M2. UE has a SLgrant for scheduling mode M1. UE generates SL MAC PDU using the dataavailable for transmission in SL LCH(s) of a destination (or of a sourceand destination pair) and transmits the generated SL MAC PDU using SLgrant (or SL SCH resources) for M1. In the SL MAC PDU, UE firstschedules data from LCH A and LCH B which are associated with schedulingmode M1, wherein data from LCH A and LCH B is included in decreasingpriority order and up to Bj (601). If there is remaining SL grant, UEthen schedules data from LCH C and LCH D which are associated withscheduling mode M2, wherein data from LCH C and LCH D is included indecreasing priority order and up to Bj (602). If there is stillremaining SL grant, UE schedules data from all SL LCHs (irrespective ofscheduling mode) in decreasing priority order (603).

Embodiment 2

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation). gNB signals the associated scheduling mode foreach SL LCH (or SL radio bearer). The signaling can be done using RRCsignaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of a destination (or of a source and destination pair) inSL MAC PDU as follows:

-   -   Schedule/include data from SL LCH(s) associated with scheduling        mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   If ‘multilplexingOtherModeAllowed’ is configured        (multilplexingOtherModeAllowed can be indicated by gNB using RRC        signaling message):    -   If there is remaining SL grant, allocate resources to the SL        LCHs with Bj>0 and associated with scheduling mode different        from scheduling mode of SL grant in a strict decreasing priority        order where SL LCHs are allocated resources up to Bj.    -   If there is still remaining SL grant, allocate resources to the        SL LCHs (irrespective of associated scheduling mode) having data        available for transmission in a strict decreasing priority order        (regardless of the value of Bj) until either the data for that        logical channel or the SL grant is exhausted, whichever comes        first. Logical channels configured with equal priority are        served equally (or up to UE implementation).

If ‘multilplexingOtherModeAllowed’ is not configured:

-   -   allocate resources to the SL LCHs associated with scheduling        mode of SL grant having data available for transmission in a        strict decreasing priority order (regardless of the value of Bj)        until either the data for that logical channel or the SL grant        is exhausted, whichever comes first. Logical channels configured        with equal priority are served equally (or up to UE        implementation).

Embodiment 3

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation). gNB signals the associated scheduling mode foreach SL LCH (or SL radio bearer). The signaling can be done using RRCsignaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of a destination (or of a source and destination pair) inSL MAC PDU as follows:

-   -   Schedule/include data from SL LCH(s) associated with scheduling        mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   If there is remaining SL grant, allocate resources to the ‘SL        LCHs with Bj>0 and associated with scheduling mode different        from scheduling mode of SL grant and for which        multilplexingOtherModeAllowed is configured’, in a strict        decreasing priority order where SL LCHs are allocated resources        up to Bj.    -   If there is still remaining SL grant, allocate resources to the        SL LCHs associated with scheduling mode of SL grant and ‘SL LCHs        associated with scheduling mode different from scheduling mode        of SL grant and for which multilplexingOtherModeAllowed’ having        data available for transmission in a strict decreasing priority        order (regardless of the value of Bj) until either the data for        that logical channel or the SL grant is exhausted, whichever        comes first. Logical channels configured with equal priority are        served equally (or up to UE implementation).

Method 4 Embodiment 1

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation) or both. gNB signals the associated scheduling modefor each SL LCH (or SL radio bearer). The signaling can be done usingRRC signaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of a destination (or of a source and destination pair) inSL MAC PDU as follows:

-   -   Schedule/include data from SL LCH(s) associated with at least        the scheduling mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   if any resources remain, all the SL LCHs are served in a strict        decreasing priority order (regardless of the value of Bj) until        either the data for that logical channel or the SL grant is        exhausted, whichever comes first. Logical channels configured        with equal priority are served equally (or up to UE        implementation).    -   If all data from SL LCHs associated with at least the scheduling        mode of the SL grant is scheduled/included AND if there is        remaining SL grant: UE schedule/include data from SL LCHs        associated with only one scheduling mode wherein the scheduling        mode is different from scheduling mode of the SL grant as        follows:    -   Allocate resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj. Parameter Bj is        maintained for every SL LCH as specified in TS 38.321.    -   if any resources remain, all the SL LCHs having data available        for transmission are served in a strict decreasing priority        order (regardless of the value of Bj) until either the data for        that logical channel or the SL grant is exhausted, whichever        comes first. Logical channels configured with equal priority are        served equally (or up to UE implementation).

FIG. 7 is an example illustration. There are four SL LCHs (LCH A, LCH B,LCH C and LCH D) associated with a destination (or source anddestination pair). LCH A and LCH B are associated with scheduling modeM1. LCH C is associated with scheduling mode M2. LCH D is associatedwith both scheduling mode M1 and M2. UE has a SL grant for schedulingmode M1. UE generates SL MAC PDU using the data available fortransmission in SL LCH(s) of a destination (or of a source anddestination pair) and transmits the generated SL MAC PDU using SL grant(or SL SCH resources) for M1. In the SL MAC PDU, UE first schedules datafrom LCH A, LCH B and LCH D which are at least associated withscheduling mode M1 (701). If all data from LCH A, LCH B and LCH D arescheduled and if there is remaining SL grant, UE schedules data from SLLCH associated with only M2 i.e., LCH C (702).

Embodiment 2

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation) or both. gNB signals the associated scheduling modefor each SL LCH (or SL radio bearer). The signaling can be done usingRRC signaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of a destination (or of a source and destination pair) inSL MAC PDU as follows:

-   -   Schedule/include data from SL LCH(s) associated with at least        the scheduling mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   if any resources remain, all the SL LCHs are served in a strict        decreasing priority order (regardless of the value of Bj) until        either the data for that logical channel or the SL grant is        exhausted, whichever comes first. Logical channels configured        with equal priority are served equally (or up to UE        implementation).    -   If ‘multilplexingOtherModeAllowed’ is configured        (multilplexingOtherModeAllowed can be indicated by gNB using RRC        signaling message):    -   If all data from SL LCHs associated with at least the scheduling        mode of the SL grant is scheduled/included AND if there is        remaining SL grant: UE schedule/include data from SL LCHs        associated with only one scheduling mode wherein the scheduling        mode is different from scheduling mode of the SL grant as        follows:    -   Allocate resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj. Parameter Bj is        maintained for every SL LCH as specified in TS 38.321.    -   if any resources remain, all the SL LCHs having data available        for transmission are served in a strict decreasing priority        order (regardless of the value of Bj) until either the data for        that logical channel or the SL grant is exhausted, whichever        comes first. Logical channels configured with equal priority are        served equally (or up to UE implementation).

Embodiment 3

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation) or both. gNB signals the associated scheduling modefor each SL LCH (or SL radio bearer). The signaling can be done usingRRC signaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of selected destination (or of a source and destinationpair) in SL MAC PDU as follows:

-   -   Schedule/include data from SL LCH(s) associated with at least        the scheduling mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   if any resources remain, all the SL LCHs are served in a strict        decreasing priority order (regardless of the value of Bj) until        either the data for that logical channel or the SL grant is        exhausted, whichever comes first. Logical channels configured        with equal priority are served equally (or up to UE        implementation).    -   if all data from SL LCHs associated with at least the scheduling        mode of the SL grant is scheduled/included AND if there is        remaining SL grant: UE schedule/include data from SL LCHs        associated with only one scheduling mode wherein the scheduling        mode is different from scheduling mode of the SL grant and for        which multilplexingOtherModeAllowed is configured        (multilplexingOtherModeAllowed can be indicated by gNB using RRC        signaling message, indication can be per SL LCH) as follows:    -   Allocate resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj. Parameter Bj is        maintained for every SL LCH as specified in TS 38.321.    -   if any resources remain, all the SL LCHs having data available        for transmission are served in a strict decreasing priority        order (regardless of the value of Bj) until either the data for        that logical channel or the SL grant is exhausted, whichever        comes first. Logical channels configured with equal priority are        served equally (or up to UE implementation).

Method 5:

Embodiment 1

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation) or both. gNB signals the associated scheduling modefor each SL LCH (or SL radio bearer). The signaling can be done usingRRC signaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of a destination (or of a source and destination pair) inSL MAC PDU as follows:

-   -   schedule/include data from SL LCH(s) associated with at least        the scheduling mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   If there is remaining SL grant, allocate resources to the SL        LCHs (irrespective of associated scheduling mode) having data        available for transmission in a strict decreasing priority order        (regardless of the value of Bj) until either the data for that        logical channel or the SL grant is exhausted, whichever comes        first. Logical channels configured with equal priority are        served equally (or up to UE implementation).

FIG. 8 is an example illustration. There are four SL LCHs (LCH A, LCH B,LCH C and LCH D) associated with a destination (or source anddestination pair). LCH A and LCH B are associated with scheduling modeM1. LCH C is associated with scheduling mode M2. LCH D is associatedwith both scheduling mode M1 and M2. UE has a SL grant for schedulingmode M1. UE generates SL MAC PDU using the data available fortransmission in SL LCH(s) of a destination (or of a source anddestination pair) and transmits the generated SL MAC PDU using SL grant(or SL SCH resources) for M1. In the SL MAC PDU, UE first schedules datafrom LCH A, LCH B and LCH D which are associated with at leastscheduling mode M1, wherein data from LCH A, LCH B and LCH D is includedin decreasing priority order and up to Bj (801). If there is remainingSL grant, UE schedules data from all SL LCHs (irrespective of schedulingmode) in decreasing priority order (802).

Embodiment 2

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation) or both. gNB signals the associated scheduling modefor each SL LCH (or SL radio bearer). The signaling can be done usingRRC signaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of a destination (or of a source and destination pair) inSL MAC PDU as follows:

-   -   schedule/include data from SL LCH(s) associated with at least        the scheduling mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   If there is remaining SL grant:    -   If ‘multilplexingOtherModeAllowed’ is configured        (multilplexingOtherModeAllowed can be indicated by gNB using RRC        signaling message):    -   allocate resources to the SL LCHs (irrespective of associated        scheduling mode) having data available for transmission in a        strict decreasing priority order (regardless of the value of Bj)        until either the data for that logical channel or the SL grant        is exhausted, whichever comes first. Logical channels configured        with equal priority are served equally (or up to UE        implementation).    -   Else    -   allocate resources to the SL LCHs associated with at least the        scheduling mode of SL grant having data available for        transmission in a strict decreasing priority order (regardless        of the value of Bj) until either the data for that logical        channel or the SL grant is exhausted, whichever comes first.        Logical channels configured with equal priority are served        equally (or up to UE implementation).

Embodiment 3

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation) or both. gNB signals the associated scheduling modefor each SL LCH (or SL radio bearer). The signaling can be done usingRRC signaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of a destination (or of a source and destination pair) inSL MAC PDU as follows:

-   -   schedule/include data from SL LCH(s) associated with at least        the scheduling mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   If there is remaining SL grant:    -   allocate resources to the SL LCHs associated with at least the        scheduling mode of SL grant and SL LCHs associated with        scheduling mode different from scheduling mode of SL grant for        which ‘multilplexingOtherModeAllowed’ is configured having data        available for transmission in a strict decreasing priority order        (regardless of the value of Bj) until either the data for that        logical channel or the SL grant is exhausted, whichever comes        first. Logical channels configured with equal priority are        served equally (or up to UE implementation).

Method 6 Embodiment 1

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation) or both. gNB signals the associated scheduling modefor each SL LCH (or SL radio bearer). The signaling can be done usingRRC signaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of a destination (or of a source and destination pair) inSL MAC PDU as follows:

-   -   Schedule/include data from SL LCH(s) associated with at least        the scheduling mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   If there is remaining SL grant, allocate resources to the SL        LCHs with Bj>0 and associated with only one scheduling mode        which is different from scheduling mode of SL grant in a strict        decreasing priority order where SL LCHs are allocated resources        up to Bj.    -   If there is still remaining SL grant, allocate resources to the        SL LCHs (irrespective of associated scheduling mode) having data        available for transmission in a strict decreasing priority order        (regardless of the value of Bj) until either the data for that        logical channel or the SL grant is exhausted, whichever comes        first. Logical channels configured with equal priority are        served equally (or up to UE implementation).

FIG. 9 is an example illustration. There are four SL LCHs (LCH A, LCH B,LCH C and LCH D) associated with a destination (or source anddestination pair). LCH A and LCH B are associated with scheduling modeM1. LCH C is associated with scheduling mode M2. LCH D is associatedwith both scheduling mode M1 and M2. UE has a SL grant for schedulingmode M1. UE generates SL MAC PDU using the data available fortransmission in SL LCH(s) of a destination (or of a source anddestination pair) and transmits the generated SL MAC PDU using SL grant(or SL SCH resources) for M1. In the SL MAC PDU, UE first schedules datafrom LCH A, LCH B and LCH D which are associated with at leastscheduling mode M1, wherein data from LCH A, LCH B and LCH D is includedin decreasing priority order and up to Bj (901). If there is remainingSL grant, UE then schedules data from LCH C which is associated withonly scheduling mode M2, wherein data from LCH C is included up to Bj(902). If there is still remaining SL grant, UE schedules data from allSL LCHs (irrespective of scheduling mode) in decreasing priority order(903).

Embodiment 2

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation) or both. gNB signals the associated scheduling modefor each SL LCH (or SL radio bearer). The signaling can be done usingRRC signaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of a destination (or of a source and destination pair) inSL MAC PDU as follows:

-   -   Schedule/include data from SL LCH(s) associated with at least        the scheduling mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   If ‘multilplexingOtherModeAllowed’ is configured        (multilplexingOtherModeAllowed can be indicated by gNB using RRC        signaling message):    -   If there is remaining SL grant, allocate resources to the SL        LCHs with Bj>0 and associated with only one scheduling mode        which is different from scheduling mode of SL grant in a strict        decreasing priority order where SL LCHs are allocated resources        up to Bj.    -   If there is still remaining SL grant, allocate resources to the        SL LCHs (irrespective of associated scheduling mode) having data        available for transmission in a strict decreasing priority order        (regardless of the value of Bj) until either the data for that        logical channel or the SL grant is exhausted, whichever comes        first. Logical channels configured with equal priority are        served equally (or up to UE implementation).    -   If ‘multilplexingOtherModeAllowed’ is not configured:    -   allocate resources to the SL LCHs associated with at least the        scheduling mode of SL grant having data available for        transmission in a strict decreasing priority order (regardless        of the value of Bj) until either the data for that logical        channel or the SL grant is exhausted, whichever comes first.        Logical channels configured with equal priority are served        equally (or up to UE implementation).

Embodiment 3

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation) or both. gNB signals the associated scheduling modefor each SL LCH (or SL radio bearer). The signaling can be done usingRRC signaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of a destination (or of a source and destination pair) inSL MAC PDU as follows:

-   -   Schedule/include data from SL LCH(s) associated with at least        the scheduling mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   If there is remaining SL grant, allocate resources to the ‘SL        LCHs with Bj>0 and associated with only one scheduling mode        which is different from scheduling mode of SL grant and for        which multilplexingOtherModeAllowed is configured’, in a strict        decreasing priority order where SL LCHs are allocated resources        up to Bj.    -   If there is still remaining SL grant, allocate resources to the        SL LCHs associated with at least the scheduling mode of SL grant        and ‘SL LCHs associated with only one scheduling mode which is        different from scheduling mode of SL grant and for which        multilplexingOtherModeAllowed’ having data available for        transmission in a strict decreasing priority order (regardless        of the value of Bj) until either the data for that logical        channel or the SL grant is exhausted, whichever comes first.        Logical channels configured with equal priority are served        equally (or up to UE implementation).

Method 7 Embodiment 1

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation). gNB signals the associated scheduling mode foreach SL LCH (or SL radio bearer). The signaling can be done using RRCsignaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of a destination (or of a source and destination pair) inSL MAC PDU as follows:

-   -   Schedule/include data from SL LCH(s) associated with scheduling        mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   if any resources remain, all the SL LCHs are served in a strict        decreasing priority order (regardless of the value of Bj) until        either the data for that logical channel or the SL grant is        exhausted, whichever comes first. Logical channels configured        with equal priority are served equally (or up to UE        implementation).    -   If the scheduling mode of SL grant is M1 and if all data from SL        LCHs associated with scheduling mode of the SL grant is        scheduled/included AND if there is remaining SL grant: UE        schedule/include data from SL LCHs associated with a scheduling        mode different from scheduling mode of the SL grant as follows:    -   Allocate resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj. Parameter Bj is        maintained for every SL LCH as specified in TS 38.321.    -   if any resources remain, all the SL LCHs having data available        for transmission are served in a strict decreasing priority        order (regardless of the value of Bj) until either the data for        that logical channel or the SL grant is exhausted, whichever        comes first. Logical channels configured with equal priority are        served equally (or up to UE implementation).

FIG. 10 is an example illustration. There are four SL LCHs (LCH A, LCHB, LCH C and LCH D) associated with a destination (or source anddestination pair). LCH A and LCH B are associated with scheduling modeM1. LCH C and LCH D are associated with scheduling mode M2.

-   -   UE has a SL grant for scheduling mode M1. UE generates SL MAC        PDU using the data available for transmission in SL LCH(s) of a        destination (or of a source and destination pair) and transmits        the generated SL MAC PDU using SL grant (or SL SCH resources)        for M1. In the SL MAC PDU, UE first schedules data from LCH A        and LCH B which are associated with scheduling mode M1 (1001).        If all data from LCH A and LCH B is scheduled and if there is        remaining SL grant, UE schedules data from SL LCHs of M2 i.e.,        LCH C and LCH D (1002).    -   UE has a SL grant for scheduling mode M2. UE generates SL MAC        PDU using the data available for transmission in SL LCH(s) of a        destination (or of a source and destination pair) and transmits        the generated SL MAC PDU using SL grant (or SL SCH resources)        for M2. In the SL MAC PDU, UE schedules data from LCH C and LCH        D which are associated with scheduling mode M2 (1011). Note that        in this case LCH associated with other scheduling mode i.e., M1        is not included.

Embodiment 2

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation). gNB signals the associated scheduling mode foreach SL LCH (or SL radio bearer). The signaling can be done using RRCsignaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of a destination (or of a source and destination pair) inSL MAC PDU as follows:

-   -   Schedule/include data from SL LCH(s) associated with scheduling        mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   if any resources remain, all the SL LCHs having data available        for transmission are served in a strict decreasing priority        order (regardless of the value of Bj) until either the data for        that logical channel or the SL grant is exhausted, whichever        comes first. Logical channels configured with equal priority are        served equally (or up to UE implementation).    -   If the scheduling mode of SL grant is M1 and If        ‘multilplexingOtherModeAllowed’ is configured        (multilplexingOtherModeAllowed can be indicated by gNB using RRC        signaling message):    -   if all data from SL LCHs associated with scheduling mode of the        SL grant is scheduled/included AND if there is remaining SL        grant: UE schedule/include data from SL LCHs associated with a        scheduling mode different from scheduling mode of the SL grant        as follows:    -   Allocate resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj. Parameter Bj is        maintained for every SL LCH as specified in TS 38.321.    -   if any resources remain, all the SL LCHs having data available        for transmission are served in a strict decreasing priority        order (regardless of the value of Bj) until either the data for        that logical channel or the SL grant is exhausted, whichever        comes first. Logical channels configured with equal priority are        served equally (or up to UE implementation).

Embodiment 3

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation). gNB signals the associated scheduling mode foreach SL LCH (or SL radio bearer). The signaling can be done using RRCsignaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of selected destination (or of a source and destinationpair) in SL MAC PDU as follows:

-   -   schedule/include data from SL LCH(s) associated with scheduling        mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   if any resources remain, all the SL LCHs having data available        for transmission are served in a strict decreasing priority        order (regardless of the value of Bj) until either the data for        that logical channel or the SL grant is exhausted, whichever        comes first. Logical channels configured with equal priority are        served equally (or up to UE implementation).    -   If the scheduling mode of SL grant is M1 and if all data from SL        LCHs associated with scheduling mode of the SL grant is        scheduled/included AND if there is remaining SL grant: UE        schedule/include data from SL LCHs associated with a scheduling        mode different from scheduling mode of the SL grant and for        which multilplexingOtherModeAllowed is configured        (multilplexingOtherModeAllowed can be indicated by gNB using RRC        signaling message, indication can be per SL LCH) as follows:    -   Allocate resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj. Parameter Bj is        maintained for every SL LCH as specified in TS 38.321.    -   if any resources remain, all the SL LCHs having data available        for transmission are served in a strict decreasing priority        order (regardless of the value of Bj) until either the data for        that logical channel or the SL grant is exhausted, whichever        comes first. Logical channels configured with equal priority are        served equally (or up to UE implementation).

Method 8 Embodiment 1

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation). gNB signals the associated scheduling mode foreach SL LCH (or SL radio bearer). The signaling can be done using RRCsignaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of a destination (or of a source and destination pair) inSL MAC PDU as follows:

-   -   schedule/include data from SL LCH(s) associated with scheduling        mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   If there is remaining SL grant:    -   If the scheduling mode of SL grant is M1, allocate resources to        the SL LCHs (irrespective of associated scheduling mode) having        data available for transmission in a strict decreasing priority        order (regardless of the value of Bj) until either the data for        that logical channel or the SL grant is exhausted, whichever        comes first. Logical channels configured with equal priority are        served equally (or up to UE implementation).    -   If the scheduling mode of SL grant is not M1, allocate resources        to the SL LCHs associated with scheduling mode of SL grant        having data available for transmission in a strict decreasing        priority order (regardless of the value of Bj) until either the        data for that logical channel or the SL grant is exhausted,        whichever comes first. Logical channels configured with equal        priority are served equally (or up to UE implementation).

FIG. 11 is an example illustration. There are four SL LCHs (LCH A, LCHB, LCH C and LCH D) associated with a destination (or source anddestination pair). LCH A and LCH B are associated with scheduling modeM1. LCH C and LCH D are associated with scheduling mode M2.

-   -   UE has a SL grant for scheduling mode M1. UE generates SL MAC        PDU using the data available for transmission in SL LCH(s) of a        destination (or of a source and destination pair) and transmits        the generated SL MAC PDU using SL grant (or SL SCH resources)        for M1. In the SL MAC PDU, UE first schedules data from LCH A        and LCH B which are associated with scheduling mode M1, wherein        data from LCH A and LCH B is included in decreasing priority        order and up to Bj (1101). If there is remaining SL grant, UE        schedules data from all SL LCHs (irrespective of scheduling        mode) in decreasing priority order (1102).    -   UE has a SL grant for scheduling mode M2. UE generates SL MAC        PDU using the data available for transmission in SL LCH(s) of a        destination (or of a source and destination pair) and transmits        the generated SL MAC PDU using SL grant (or SL SCH resources)        for M2. In the SL MAC PDU, UE first schedules data from LCH C        and LCH D which are associated with scheduling mode M2, wherein        data from LCH C and LCH D is included in decreasing priority        order and up to Bj (1111). If there is remaining SL grant, UE        schedules data from all SL LCHs (irrespective of scheduling        mode) in decreasing priority order (1112).

Embodiment 2

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation). gNB signals the associated scheduling mode foreach SL LCH (or SL radio bearer). The signaling can be done using RRCsignaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of a destination (or of a source and destination pair) inSL MAC PDU as follows:

-   -   schedule/include data from SL LCH(s) associated with scheduling        mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   If there is remaining SL grant:    -   If ‘multilplexingOtherModeAllowed’ is configured        (multilplexingOtherModeAllowed can be indicated by gNB using RRC        signaling message) and If the scheduling mode of SL grant is M1:    -   allocate resources to the SL LCHs (irrespective of associated        scheduling mode) having data available for transmission in a        strict decreasing priority order (regardless of the value of Bj)        until either the data for that logical channel or the SL grant        is exhausted, whichever comes first. Logical channels configured        with equal priority are served equally (or up to UE        implementation).    -   Else    -   allocate resources to the SL LCHs associated with scheduling        mode of SL grant having data available for transmission in a        strict decreasing priority order (regardless of the value of Bj)        until either the data for that logical channel or the SL grant        is exhausted, whichever comes first. Logical channels configured        with equal priority are served equally (or up to UE        implementation).

Embodiment 3

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation). gNB signals the associated scheduling mode foreach SL LCH (or SL radio bearer). The signaling can be done using RRCsignaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of a destination (or of a source and destination pair) inSL MAC PDU as follows:

-   -   schedule/include data from SL LCH(s) associated with scheduling        mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   If there is remaining SL grant:    -   If the scheduling mode of SL grant is M1:    -   allocate resources to the SL LCHs associated with scheduling        mode of SL grant and SL LCHs associated with scheduling mode        different from scheduling mode of SL grant for which        ‘multilplexingOtherModeAllowed’ is configured having data        available for transmission in a strict decreasing priority order        (regardless of the value of Bj) until either the data for that        logical channel or the SL grant is exhausted, whichever comes        first. Logical channels configured with equal priority are        served equally (or up to UE implementation).    -   Else    -   allocate resources to the SL LCHs associated with scheduling        mode of SL grant having data available for transmission in a        strict decreasing priority order (regardless of the value of Bj)        until either the data for that logical channel or the SL grant        is exhausted, whichever comes first. Logical channels configured        with equal priority are served equally (or up to UE        implementation).

Method 9 Embodiment 1

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation). gNB signals the associated scheduling mode foreach SL LCH (or SL radio bearer). The signaling can be done using RRCsignaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of a destination (or of a source and destination pair) inSL MAC PDU as follows:

-   -   Schedule/include data from SL LCH(s) associated with scheduling        mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   If the scheduling mode of SL grant is M1 and If there is        remaining SL grant, allocate resources to the SL LCHs with Bj>0        and associated with scheduling mode different from scheduling        mode of SL grant in a strict decreasing priority order where SL        LCHs are allocated resources up to Bj.    -   If there is still remaining SL grant,    -   If the scheduling mode of SL grant is M1, allocate resources to        the SL LCHs (irrespective of associated scheduling mode) having        data available for transmission in a strict decreasing priority        order (regardless of the value of Bj) until either the data for        that logical channel or the SL grant is exhausted, whichever        comes first. Logical channels configured with equal priority are        served equally (or up to UE implementation).    -   If the scheduling mode of SL grant is not M1, allocate resources        to the SL LCHs associated with scheduling mode of SL grant        having data available for transmission in a strict decreasing        priority order (regardless of the value of Bj) until either the        data for that logical channel or the SL grant is exhausted,        whichever comes first. Logical channels configured with equal        priority are served equally (or up to UE implementation).

FIG. 12 is an example illustration. There are four SL LCHs (LCH A, LCHB, LCH C and LCH D) associated with a destination (or source anddestination pair). LCH A and LCH B are associated with scheduling modeM1. LCH C and LCH D are associated with scheduling mode M2.

-   -   UE has a SL grant for scheduling mode M1. UE generates SL MAC        PDU using the data available for transmission in SL LCH(s) of a        destination (or of a source and destination pair) and transmits        the generated SL MAC PDU using SL grant (or SL SCH resources)        for M1. In the SL MAC PDU, UE first schedules data from LCH A        and LCH B which are associated with scheduling mode M1, wherein        data from LCH A and LCH B is included in decreasing priority        order and up to Bj (1201). If there is remaining SL grant, UE        then schedules data from LCH C and LCH D which are associated        with scheduling mode M2, wherein data from LCH C and LCH D is        included in decreasing priority order and up to Bj (1202). If        there is still remaining SL grant, UE schedules data from all SL        LCHs (irrespective of scheduling mode) in decreasing priority        order (1203).    -   UE has a SL grant for scheduling mode M2. UE generates SL MAC        PDU using the data available for transmission in SL LCH(s) of a        destination (or of a source and destination pair) and transmits        the generated SL MAC PDU using SL grant (or SL SCH resources)        for M1. In the SL MAC PDU, UE first schedules data from LCH C        and LCH D which are associated with scheduling mode M1, wherein        data from LCH C and LCH D is included in decreasing priority        order and up to Bj (1211). If there is remaining SL grant, UE        then schedules data from LCH C and LCH D which are associated        with scheduling mode M2, wherein data from LCH C and LCH D is        included in decreasing priority order (1212).

Embodiment 2

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation). gNB signals the associated scheduling mode foreach SL LCH (or SL radio bearer). The signaling can be done using RRCsignaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of a destination (or of a source and destination pair) inSL MAC PDU as follows:

-   -   Schedule/include data from SL LCH(s) associated with scheduling        mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   If the scheduling mode of SL grant is M1 and If        ‘multilplexingOtherModeAllowed’ is configured        (multilplexingOtherModeAllowed can be indicated by gNB using RRC        signaling message):    -   If there is remaining SL grant, allocate resources to the SL        LCHs with Bj>0 and associated with scheduling mode different        from scheduling mode of SL grant in a strict decreasing priority        order where SL LCHs are allocated resources up to Bj.    -   If there is still remaining SL grant, allocate resources to the        SL LCHs (irrespective of associated scheduling mode) having data        available for transmission in a strict decreasing priority order        (regardless of the value of Bj) until either the data for that        logical channel or the SL grant is exhausted, whichever comes        first. Logical channels configured with equal priority are        served equally (or up to UE implementation).    -   else:        -   allocate resources to the SL LCHs associated with scheduling            mode of SL grant having data available for transmission in a            strict decreasing priority order (regardless of the value of            Bj) until either the data for that logical channel or the SL            grant is exhausted, whichever comes first. Logical channels            configured with equal priority are served equally (or up to            UE implementation).

Embodiment 3

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation). gNB signals the associated scheduling mode foreach SL LCH (or SL radio bearer). The signaling can be done using RRCsignaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of a destination (or of a source and destination pair) inSL MAC PDU as follows:

-   -   Schedule/include data from SL LCH(s) associated with scheduling        mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   If the scheduling mode of SL grant is M1 and If there is        remaining SL grant, allocate resources to the ‘SL LCHs with Bj>0        and associated with scheduling mode different from scheduling        mode of SL grant and for which multilplexingOtherModeAllowed is        configured’, in a strict decreasing priority order where SL LCHs        are allocated resources up to Bj.    -   If there is still remaining SL grant,    -   If the scheduling mode of SL grant is M1 and allocate resources        to the SL LCHs associated with scheduling mode of SL grant and        ‘SL LCHs associated with scheduling mode different from        scheduling mode of SL grant and for which        multilplexingOtherModeAllowed’ having data available for        transmission in a strict decreasing priority order (regardless        of the value of Bj) until either the data for that logical        channel or the SL grant is exhausted, whichever comes first.        Logical channels configured with equal priority are served        equally (or up to UE implementation).    -   If the scheduling mode of SL grant is not M1, allocate resources        to the SL LCHs associated with scheduling mode of SL grant        having data available for transmission in a strict decreasing        priority order (regardless of the value of Bj) until either the        data for that logical channel or the SL grant is exhausted,        whichever comes first. Logical channels configured with equal        priority are served equally (or up to UE implementation).

Method 10 Embodiment 1

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation) or both. gNB signals the associated scheduling modefor each SL LCH (or SL radio bearer). The signaling can be done usingRRC signaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of a destination (or of a source and destination pair) inSL MAC PDU as follows:

-   -   Schedule/include data from SL LCH(s) associated with at least        the scheduling mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   if any resources remain, all the SL LCHs are served in a strict        decreasing priority order (regardless of the value of Bj) until        either the data for that logical channel or the SL grant is        exhausted, whichever comes first. Logical channels configured        with equal priority are served equally (or up to UE        implementation).    -   If the scheduling mode of SL grant is M1 and if all data from SL        LCHs associated with at least the scheduling mode of the SL        grant is scheduled/included AND if there is remaining SL grant:        UE schedule/include data from SL LCHs associated with only one        scheduling mode which is different from scheduling mode of the        SL grant as follows:    -   Allocate resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj. Parameter Bj is        maintained for every SL LCH as specified in TS 38.321.    -   if any resources remain, all the SL LCHs having data available        for transmission are served in a strict decreasing priority        order (regardless of the value of Bj) until either the data for        that logical channel or the SL grant is exhausted, whichever        comes first. Logical channels configured with equal priority are        served equally (or up to UE implementation).

FIG. 11 is an example illustration. There are four SL LCHs (LCH A, LCHB, LCH C and LCH D) associated with a destination (or source anddestination pair). LCH A and LCH B are associated with scheduling modeM1. LCH D is associated with scheduling mode M2. LCH is associated withscheduling mode M1 and M2.

-   -   UE has a SL grant for scheduling mode M1. UE generates SL MAC        PDU using the data available for transmission in SL LCH(s) of a        destination (or of a source and destination pair) and transmits        the generated SL MAC PDU using SL grant (or SL SCH resources)        for M1. In the SL MAC PDU, UE first schedules data from LCH A,        LCH B and LCH C which are associated with scheduling mode M1        (1301). If all data from LCH A, LCH B and LCH C is scheduled and        if there is remaining SL grant, UE schedules data from SL LCH of        only M2 i.e., LCH D (1302).    -   UE has a SL grant for scheduling mode M2. UE generates SL MAC        PDU using the data available for transmission in SL LCH(s) of a        destination (or of a source and destination pair) and transmits        the generated SL MAC PDU using SL grant (or SL SCH resources)        for M2. In the SL MAC PDU, UE schedules data from LCH D which        are associated with scheduling mode M2 (1311). Note that in this        case LCH associated with other scheduling mode i.e., M1 is not        included.

Embodiment 2

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation) or both. gNB signals the associated scheduling modefor each SL LCH (or SL radio bearer). The signaling can be done usingRRC signaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of a destination (or of a source and destination pair) inSL MAC PDU as follows:

-   -   Schedule/include data from SL LCH(s) associated with at least        the scheduling mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   if any resources remain, all the SL LCHs having data available        for transmission are served in a strict decreasing priority        order (regardless of the value of Bj) until either the data for        that logical channel or the SL grant is exhausted, whichever        comes first. Logical channels configured with equal priority are        served equally (or up to UE implementation).    -   If the scheduling mode of SL grant is M1 and If        ‘multilplexingOtherModeAllowed’ is configured        (multilplexingOtherModeAllowed can be indicated by gNB using RRC        signaling message):    -   if all data from SL LCHs associated with at least the scheduling        mode of the SL grant is scheduled/included AND if there is        remaining SL grant: UE schedule/include data from SL LCHs        associated with only one scheduling mode which is different from        scheduling mode of the SL grant as follows:    -   Allocate resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj. Parameter Bj is        maintained for every SL LCH as specified in TS 38.321.    -   if any resources remain, all the SL LCHs having data available        for transmission are served in a strict decreasing priority        order (regardless of the value of Bj) until either the data for        that logical channel or the SL grant is exhausted, whichever        comes first. Logical channels configured with equal priority are        served equally (or up to UE implementation).

Embodiment 3

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation) or both. gNB signals the associated scheduling modefor each SL LCH (or SL radio bearer). The signaling can be done usingRRC signaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of selected destination (or of a source and destinationpair) in SL MAC PDU as follows:

-   -   schedule/include data from SL LCH(s) associated with at least        the scheduling mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   if any resources remain, all the SL LCHs having data available        for transmission are served in a strict decreasing priority        order (regardless of the value of Bj) until either the data for        that logical channel or the SL grant is exhausted, whichever        comes first. Logical channels configured with equal priority are        served equally (or up to UE implementation).    -   If the scheduling mode of SL grant is M1 and if all data from SL        LCHs associated with at least the scheduling mode of the SL        grant is scheduled/included AND if there is remaining SL grant:        UE schedule/include data from SL LCHs associated with only one        scheduling mode which is different from scheduling mode of the        SL grant and for which multilplexingOtherModeAllowed is        configured (multilplexingOtherModeAllowed can be indicated by        gNB using RRC signaling message, indication can be per SL LCH)        as follows:    -   Allocate resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj. Parameter Bj is        maintained for every SL LCH as specified in TS 38.321.    -   if any resources remain, all the SL LCHs having data available        for transmission are served in a strict decreasing priority        order (regardless of the value of Bj) until either the data for        that logical channel or the SL grant is exhausted, whichever        comes first. Logical channels configured with equal priority are        served equally (or up to UE implementation).

Method 11 Embodiment 1

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation) or both. gNB signals the associated scheduling modefor each SL LCH (or SL radio bearer). The signaling can be done usingRRC signaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of a destination (or of a source and destination pair) inSL MAC PDU as follows:

-   -   schedule/include data from SL LCH(s) associated with at least        scheduling mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   If there is remaining SL grant:    -   If the scheduling mode of SL grant is M1, allocate resources to        the SL LCHs (irrespective of associated scheduling mode) having        data available for transmission in a strict decreasing priority        order (regardless of the value of Bj) until either the data for        that logical channel or the SL grant is exhausted, whichever        comes first. Logical channels configured with equal priority are        served equally (or up to UE implementation).    -   If the scheduling mode of SL grant is not M1, allocate resources        to the SL LCHs associated with at least the scheduling mode of        SL grant having data available for transmission in a strict        decreasing priority order (regardless of the value of Bj) until        either the data for that logical channel or the SL grant is        exhausted, whichever comes first. Logical channels configured        with equal priority are served equally (or up to UE        implementation).

FIG. 14 is an example illustration. There are four SL LCHs (LCH A, LCHB, LCH C and LCH D) associated with a destination (or source anddestination pair). LCH A and LCH B are associated with scheduling modeM1. LCH D is associated with scheduling mode M2. LCH C is associatedwith scheduling mode M1 and M2.

-   -   UE has a SL grant for scheduling mode M1. UE generates SL MAC        PDU using the data available for transmission in SL LCH(s) of a        destination (or of a source and destination pair) and transmits        the generated SL MAC PDU using SL grant (or SL SCH resources)        for M1. In the SL MAC PDU, UE first schedules data from LCH A,        LCH B and LCH C in decreasing priority order up to Bj (1401). If        there is remaining SL grant, UE schedules data from LCH A, LCH        B, LCH C and LCH D in decreasing priority order without        considering Bj (1402).    -   UE has a SL grant for scheduling mode M2. UE generates SL MAC        PDU using the data available for transmission in SL LCH(s) of a        destination (or of a source and destination pair) and transmits        the generated SL MAC PDU using SL grant (or SL SCH resources)        for M2. In the SL MAC PDU, UE first schedules data from LCH C        and LCH D in decreasing priority order up to Bj (1411). If there        is remaining SL grant, UE schedules data from LCH C and LCH D in        decreasing priority order without considering Bj (1412).

Embodiment 2

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation). gNB signals the associated scheduling mode foreach SL LCH (or SL radio bearer). The signaling can be done using RRCsignaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of a destination (or of a source and destination pair) inSL MAC PDU as follows:

-   -   schedule/include data from SL LCH(s) associated with at least        the scheduling mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   If there is remaining SL grant:    -   If ‘multilplexingOtherModeAllowed’ is configured        (multilplexingOtherModeAllowed can be indicated by gNB using RRC        signaling message) and If the scheduling mode of SL grant is M1:    -   allocate resources to the SL LCHs (irrespective of associated        scheduling mode) having data available for transmission in a        strict decreasing priority order (regardless of the value of Bj)        until either the data for that logical channel or the SL grant        is exhausted, whichever comes first. Logical channels configured        with equal priority are served equally (or up to UE        implementation).    -   Else    -   allocate resources to the SL LCHs associated with at least the        scheduling mode of SL grant having data available for        transmission in a strict decreasing priority order (regardless        of the value of Bj) until either the data for that logical        channel or the SL grant is exhausted, whichever comes first.        Logical channels configured with equal priority are served        equally (or up to UE implementation).

Embodiment 3

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation). gNB signals the associated scheduling mode foreach SL LCH (or SL radio bearer). The signaling can be done using RRCsignaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of a destination (or of a source and destination pair) inSL MAC PDU as follows:

-   -   schedule/include data from SL LCH(s) associated with at least        the scheduling mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   If there is remaining SL grant:    -   If the scheduling mode of SL grant is M1:    -   allocate resources to the SL LCHs associated with at least the        scheduling mode of SL grant and SL LCHs associated with only one        scheduling mode which is different from scheduling mode of SL        grant for which ‘multilplexingOtherModeAllowed’ is configured        having data available for transmission in a strict decreasing        priority order (regardless of the value of Bj) until either the        data for that logical channel or the SL grant is exhausted,        whichever comes first. Logical channels configured with equal        priority are served equally (or up to UE implementation).    -   Else    -   allocate resources to the SL LCHs associated with at least the        scheduling mode of SL grant having data available for        transmission in a strict decreasing priority order (regardless        of the value of Bj) until either the data for that logical        channel or the SL grant is exhausted, whichever comes first.        Logical channels configured with equal priority are served        equally (or up to UE implementation).

Method 12 Embodiment 1

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation) or both. gNB signals the associated scheduling modefor each SL LCH (or SL radio bearer). The signaling can be done usingRRC signaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of a destination (or of a source and destination pair) inSL MAC PDU as follows:

-   -   Schedule/include data from SL LCH(s) associated with at least        the scheduling mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   If the scheduling mode of SL grant is M1 and If there is        remaining SL grant, allocate resources to the SL LCHs with Bj>0        and associated with only one scheduling mode which is different        from scheduling mode of SL grant in a strict decreasing priority        order where SL LCHs are allocated resources up to Bj.    -   If there is still remaining SL grant,    -   If the scheduling mode of SL grant is M1, allocate resources to        the SL LCHs (irrespective of associated scheduling mode) having        data available for transmission in a strict decreasing priority        order (regardless of the value of Bj) until either the data for        that logical channel or the SL grant is exhausted, whichever        comes first. Logical channels configured with equal priority are        served equally (or up to UE implementation).    -   If the scheduling mode of SL grant is not M1, allocate resources        to the SL LCHs associated with at least the scheduling mode of        SL grant having data available for transmission in a strict        decreasing priority order (regardless of the value of Bj) until        either the data for that logical channel or the SL grant is        exhausted, whichever comes first. Logical channels configured        with equal priority are served equally (or up to UE        implementation).

FIG. 15 is an example illustration. There are four SL LCHs (LCH A, LCHB, LCH C and LCH D) associated with a destination (or source anddestination pair).

-   -   UE has a SL grant for scheduling mode M1. UE generates SL MAC        PDU using the data available for transmission in SL LCH(s) of a        destination (or of a source and destination pair) and transmits        the generated SL MAC PDU using SL grant (or SL SCH resources)        for M1. In the SL MAC PDU, UE first schedules data from LCH A,        LCH B and LCH C in decreasing priority order up to Bj (1501). If        there is remaining SL grant, UE schedules data from LCH B up to        Bj (1502). If there is still remaining SL grant, UE schedules        data from LCH A, LCH B, LCH C and LCH D in decreasing priority        order without considering Bj (1503).    -   UE has a SL grant for scheduling mode M2. UE generates SL MAC        PDU using the data available for transmission in SL LCH(s) of a        destination (or of a source and destination pair) and transmits        the generated SL MAC PDU using SL grant (or SL SCH resources)        for M2. In the SL MAC PDU, UE first schedules data from LCH C        and LCH D in decreasing priority order up to Bj (1511). If there        is remaining SL grant, UE schedules data from LCH C and LCH D in        decreasing priority order without considering Bj (1512).

Embodiment 2

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation) or both. gNB signals the associated scheduling modefor each SL LCH (or SL radio bearer). The signaling can be done usingRRC signaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of a destination (or of a source and destination pair) inSL MAC PDU as follows:

-   -   Schedule/include data from SL LCH(s) associated with at least        the scheduling mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   If the scheduling mode of SL grant is M1 and If        ‘multilplexingOtherModeAllowed’ is configured        (multilplexingOtherModeAllowed can be indicated by gNB using RRC        signaling message):    -   If there is remaining SL grant, allocate resources to the SL        LCHs with Bj>0 and associated with only one scheduling mode        which is different from scheduling mode of SL grant in a strict        decreasing priority order where SL LCHs are allocated resources        up to Bj.    -   If there is still remaining SL grant, allocate resources to the        SL LCHs (irrespective of associated scheduling mode) having data        available for transmission in a strict decreasing priority order        (regardless of the value of Bj) until either the data for that        logical channel or the SL grant is exhausted, whichever comes        first. Logical channels configured with equal priority are        served equally (or up to UE implementation).    -   else:        -   allocate resources to the SL LCHs associated with at least            the scheduling mode of SL grant having data available for            transmission in a strict decreasing priority order            (regardless of the value of Bj) until either the data for            that logical channel or the SL grant is exhausted, whichever            comes first. Logical channels configured with equal priority            are served equally (or up to UE implementation).

Embodiment 3

Sidelink logical channels (SL LCHs) or radio bearers are associated withscheduling modes. Each SL LCH is either associated with scheduling modeM1 (i.e., Scheduled Resource Allocation) or mode M2 (i.e., UE autonomousResource Allocation) or both. gNB signals the associated scheduling modefor each SL LCH (or SL radio bearer). The signaling can be done usingRRC signaling message (e.g., RRC Reconfiguration message).

UE generates SL MAC PDU using the data available for transmission in SLLCH(s) of a destination (or of a source and destination pair) andtransmits the generated SL MAC PDU using SL grant (or SL SCH resources).The destination (or of a source and destination pair) is selected asspecified in TS 38.321.

In one embodiment of this disclosure, for a SL grant, UE includes thedata available from various SL LCHs (having data available fortransmission) of a destination (or of a source and destination pair) inSL MAC PDU as follows:

-   -   Schedule/include data from SL LCH(s) associated with at least        the scheduling mode of the SL grant as follows:    -   Allocate resources to SL MAC CE(s) of selected destination (or        source and destination pair) and SL LCHs with Bj>0 in decreasing        priority, where SL LCHs are allocated resources up to Bj.        Parameter Bj is maintained for every SL LCH as specified in TS        38.321. Alternately, allocate resources to SL LCHs with Bj>0 in        decreasing priority, where SL LCHs are allocated resources up to        Bj. Alternately, first allocate resources to SL MAC CE(s) of        selected destination (or source and destination pair), then        allocated resources to SL LCHs with Bj>0 in decreasing priority,        where SL LCHs are allocated resources up to Bj.    -   If the scheduling mode of SL grant is M1 and If there is        remaining SL grant, allocate resources to the ‘SL LCHs with Bj>0        and associated with only one scheduling mode which is different        from scheduling mode of SL grant and for which        multilplexingOtherModeAllowed is configured’, in a strict        decreasing priority order where SL LCHs are allocated resources        up to Bj.    -   If there is still remaining SL grant,    -   If the scheduling mode of SL grant is M1 and allocate resources        to the SL LCHs associated with scheduling mode of SL grant and        ‘SL LCHs associated with only one scheduling mode which is        different from scheduling mode of SL grant and for which        multilplexingOtherModeAllowed’ having data available for        transmission in a strict decreasing priority order (regardless        of the value of Bj) until either the data for that logical        channel or the SL grant is exhausted, whichever comes first.        Logical channels configured with equal priority are served        equally (or up to UE implementation).    -   If the scheduling mode of SL grant is not M1, allocate resources        to the SL LCHs associated with at least the scheduling mode of        SL grant having data available for transmission in a strict        decreasing priority order (regardless of the value of Bj) until        either the data for that logical channel or the SL grant is        exhausted, whichever comes first. Logical channels configured        with equal priority are served equally (or up to UE        implementation).

Preambles for Small Data Transmission

For small data transmission, Random Access Procedure is initiated. Uponreceiving the random access preamble, gNB should be able to distinguishwhether the UE has initiated the random access for small datatransmission or not.

In the LTE system, preambles for small data transmission are configuredper CE levels. There can be one or more CE levels. The preambles fornormal random access (i.e., other than small data transmission) aresignaling by eNB using two parameters: firstPreamble and lastPreamble.These parameters are signaled for each CE level. firstPreamble andlastPreamble indicates preamble index. For a given CE level, thepreambles from firstPreamble to lastPreamble are used for normal randomaccess. The preambles for random access for small data transmission areindicated by eNB by signaling additional parameter: edt-lastPreamble.For the concerned CE level, if PRACH resources configured for small datatransmission are different from the PRACH resources configured for nonsmall data transmission for all CE levels and for small datatransmission for all other CE levels, the preambles for small datatransmission are the preambles firstPreamble to edt-lastPreamble.Otherwise, the preambles for small data transmission are the preambleslastPreamble+1 to edt-LastPreamble.

In the NR system, the preambles for random access are indicated by gNBby signaling parameters: ssb-perRACH-Occasion and CB-PreamblesPerSSB inRACH configuration. In an UL BWP, 4S RA (4 step random access) for SDTand/or 4S RA for Non SDT (ex. for a normal mobile communication) and/or2S RA (2 step random access) for SDT and/or 2S RA for non SDT can beconfigured. ROs may or may not be shared between one or more of these RAtypes i.e., 4SRA for SDT, 4S RA for Non SDT, 2S RA for SDT, 2S RA fornon SDT. The issue is how to determine which preambles/SSB/RO are usedfor 4S RA SDT and 2S RA SDT. Explicitly indicating each preamble indexfor each SSB/RO will lead to significant signaling overhead.

Embodiment 1

4 step RACH is configured in the UL BWP and small data transmission issupported using 4 step RACH in the UL BWP. Small data transmission isconsidered supported using 4 step RACH in the UL BWP, if that UL BWPconfiguration includes 4 step RACH configuration for small datatransmission. UL BWP configuration can be received from gNB in systeminformation or RRC reconfiguration message. Note that here UL BWP refersto BWP on which UE transmits PRACH for small data transmission. This ULBWP can be initial UL BWP or another UL BWP indicated by gNB for smalldata transmission. 2 step RACH is not configured in this UL BWP (i.e.,neither configured for small data transmission, nor for regular 2 steprandom access). In the below description the parameters correspond tothe UL BWP for small data transmission.

For 4 step RACH, if ROs configured for small data transmission areshared with ROs configured for regular 4 step random access (i.e., nonsmall data transmission):

UE determines the starting preamble index for small data transmission asfollows:

Starting preamble index (S)=R1, where R1 is CB-PreamblesPerSSBconfigured (e.g., in the rach-ConfigCommon IE) for regular 4 step randomaccess. N1 is number of SSBs per RACH occasion configured (e.g., in therach-ConfigCommon IE) for regular 4 step random access.

UE determines preambles for each SSB as follows:

If N1<1: Preambles starting from S to S+CB-PreamblesPerSSB-SDT (X)−1 areused for small data transmission. In other words, X contention basedpreambles with consecutive indexes associated with the SSB per validPRACH occasion start from S.

If N1>=1, X contention based preambles with consecutive indexesassociated with SS/PBCH block n, 0≤n≤N1−1, per valid PRACH occasionstart from preamble index ‘S+n·N_(preamble) ^(total)/N1, whereN_(preamble) ^(total) is provided by totalNumberOfRA-Preambles.totalNumberOfRA-Preambles is the total number of RA preambles configuredfor regular random access.

FIG. 16 and FIG. 17 are example illustrations.

-   -   In an embodiment, if prach-ConfigIndex is not signaled by gNB        for small data transmission, UE uses the prach-ConfigIndex        configured for regular random access to determine ROs. This        means that if prach-ConfigIndex is not signaled for small data        transmission, ROs configured for small data transmission are        shared with ROs configured for regular random access (i.e., non        small data transmission).

For 4 step RACH, if ROs configured for small data transmission are notshared with ROs configured for regular 4 step random access (i.e., nonsmall data transmission):

UE first determine starting preamble index for small data transmissionas follows:

Starting preamble index (S)=0.

CB-PreamblesPerSSB-SDT (X) and ssb-perRACH-Occasion-SDT (Y) isconfigured/signaled (e.g., in the rach-ConfigCommon-SDT IE) by gNB forsmall data transmission using 4 step RACH.

UE then determine preambles for each SSB as follows:

If Y<1: Preambles starting from S to S+CB-PreamblesPerSSB-SDT (X)−1 areused for small data transmission. In other words, X contention basedpreambles with consecutive indexes associated with the SSB per validPRACH occasion start from S.

If Y>=1, X contention based preambles with consecutive indexesassociated with SS/PBCH block n, 0≤n≤Y−1, per valid PRACH occasion startfrom preamble index ‘S+n·N_(preamble) ^(total)/Y, where N_(preamble)^(total) is provided by totalNumberOfRA-Preambles-SDT.totalNumberOfRA-Preambles-SDT is the total number of RA preamblesconfigured for small data transmission.

In an embodiment, if prach-ConfigIndex is signaled for small datatransmission, UE uses the prach-ConfigIndex configured for small datatransmission to determine ROs. This means that if prach-ConfigIndex issignaled for small data transmission, ROs configured for small datatransmission are not shared with ROs configured for regular randomaccess (i.e., non small data transmission)

During the random access procedure initiated for small datatransmission, for each random access attempt, UE first select SSB (SSBwith highest SS-RSRP or SSB with SS-RSRP above a configured threshold orany SSB if there is no SSB with SS-RSRP above threshold) and thenpreamble and RO corresponding to selected SSB wherein preamble isselected from set of preambles corresponding to the selected SSB asdetermined above. Mapping between ROs and SSBs is determined as inregular random access procedure. UE then transmit selected PRACHpreamble and selected RO.

Embodiment 2

2 step RACH is configured in the UL BWP and small data transmission issupported using 2 step RACH in the UL BWP. Small data transmission isconsidered supported using 2 step RACH in the UL BWP, if that UL BWPconfiguration includes 2 step RACH configuration for small datatransmission. UL BWP configuration can be received from gNB in systeminformation or RRC reconfiguration message. Note that here UL BWP refersto BWP on which UE transmits PRACH for small data transmission. This ULBWP can be initial UL BWP or another UL BWP indicated by gNB for smalldata transmission. 4 step RACH is not configured in this UL BWP (i.e.,neither configured for small data transmission, nor for regular 4 steprandom access). In the below description the parameters correspond tothe UL BWP for small data transmission.

For 2 step RACH, if ROs configured for small data transmission areshared with ROs configured for regular 2 step random access (i.e., nonsmall data transmission):

UE determines the starting preamble index for small data transmission asfollows:

Starting preamble index (S)=R1, where R1 is CB-PreamblesPerSSBconfigured (e.g., in the rach-ConfigCommon2Step IE) for regular 2 steprandom access. N1 is ssb-perRACH-Occasion

CB-PreamblesPerSSB-SDT (X) is configured/signaled (e.g., in therach-ConfigCommon2Step-SDT IE) by gNB for small data transmission using2 step RACH.

UE determines preambles for each SSB as follows:

If N1<1: Preambles starting from S to S+CB-PreamblesPerSSB-SDT (X)−1 areused for small data transmission. In other words, X contention basedpreambles with consecutive indexes associated with the SSB per validPRACH occasion start from S.

If N1>=1, X contention based preambles with consecutive indexesassociated with SS/PBCH block n, 0≤n≤N1−1, per valid PRACH occasionstart from preamble index ‘S+n·N_(preamble) ^(total)/N1, whereN_(preamble) ^(total) is provided by totalNumberOfRA-Preambles.totalNumberOfRA-Preambles is the total number of RA preambles configuredfor regular 2 step random access.

FIG. 18 and FIG. 19 are example illustrations.

-   -   In an embodiment, if prach-ConfigIndex is not signaled for small        data transmission, UE uses the prach-ConfigIndex configured for        regular 2 step random access to determine ROs. This means that        if prach-ConfigIndex is not signaled for small data        transmission, ROs configured for small data transmission are        shared with ROs configured for regular 2 step random access        (i.e., non small data transmission)

For 2 step RACH, if ROs configured for small data transmission are notshared with ROs configured for regular 2 step random access (i.e., nonsmall data transmission):

UE determines the starting preamble index for small data transmission asfollows:

Starting preamble index (S)=0.

CB-PreamblesPerSSB-SDT (X) and ssb-perRACH-Occasion-SDT (Y) isconfigured/signaled (e.g., in the rach-ConfigCommon2Step-SDT IE) by gNBfor small data transmission using 2 step RACH.

UE determines preambles for each SSB as follows:

If Y<1: Preambles starting from S to S+CB-PreamblesPerSSB-SDT (X)−1 areused for small data transmission. In other words, X contention basedpreambles with consecutive indexes associated with the SSB per validPRACH occasion start from S.

If Y>=1, X contention based preambles with consecutive indexesassociated with SS/PBCH block n, 0≤n≤Y−1, per valid PRACH occasion startfrom preamble index ‘S+n·N_(preamble) ^(total)/Y, where N_(preamble)^(total) is provided by totalNumberOfRA-Preambles-SDT.totalNumberOfRA-Preambles-SDT is the total number of RA preamblesconfigured for small data transmission.

-   -   In an embodiment, if prach-ConfigIndex is signaled for small        data transmission, UE uses the prach-ConfigIndex configured for        small data transmission to determine ROs. This means that if        prach-ConfigIndex is signaled for small data transmission, ROs        configured for small data transmission are not shared with ROs        configured for regular 2 step random access (i.e., non small        data transmission).

During the random access procedure initiated for small datatransmission, for each random access attempt UE first select SSB (SSBwith highest SS-RSRP or SSB with SS-RSRP above a configured threshold orany SSB if there is no SSB with SS-RSRP above threshold) and thenpreamble and RO corresponding to selected SSB wherein preamble isselected from set of preambles determined above corresponding to theselected SSB. Mapping between ROs and SSBs is determined as in regularrandom access procedure. UE then transmit selected PRACH preamble andselected RO. UE shall also select PUSCH occasion from PUSCH occasionsconfigured for small data transmission and transmit MsgA MAC PDU whichinclude small data i.e., MAC SDU(s) for DRB.

Embodiment 3

Both 2 step and 4 step RACH are configured in the UL BWP. ROs are sharedbetween 2 step and 4 step RACH. Small data transmission is supported inthe UL BWP. This UL BWP can be initial UL BWP or another UL BWPindicated by gNB for small data transmission.

Case 1: Small data transmission is supported in the UL BWP using 4 stepRACH and not supported for 2 step RACH.

For 4 step RACH, if ROs configured for small data transmission areshared with ROs configured for regular random access (i.e., non smalldata transmission):

UE determines the starting preamble index for small data transmission asfollows:

Starting preamble index (S)=R1+R2, where N1 is ssb-perRACH-Occasion andR1 is CB-PreamblesPerSSB configured (e.g., in the rach-ConfigCommon IE)for regular 4 step random access, R2 is CB-PreamblesPerSSB configured(e.g., in the rach-ConfigCommon2Step IE) for regular 2 step randomaccess

CB-PreamblesPerSSB-SDT (X) is configured/signaled (e.g., in therach-ConfigCommon-SDT IE) by gNB for small data transmission using 4step RACH.

UE determines preambles for each SSB as follows:

If N1<1: Preambles starting from S to S+CB-PreamblesPerSSB-SDT (X)−1 areused for small data transmission. In other words, X contention basedpreambles with consecutive indexes associated with the SSB per validPRACH occasion start from S.

If N1>=1, X contention based preambles with consecutive indexesassociated with SS/PBCH block n, 0≤n≤N1−1, per valid PRACH occasionstart from preamble index ‘S+n·N_(preamble) ^(total)/N1, whereN_(preamble) ^(total) is provided by totalNumberOfRA-Preambles.totalNumberOfRA-Preambles is the total number of RA preambles configuredfor regular random access in the rach-ConfigCommon IE.

FIG. 20 and FIG. 21 are example illustrations.

-   -   In an embodiment, if prach-ConfigIndex is not signaled for small        data transmission, UE uses the prach-ConfigIndex configured for        regular 4 step random access to determine ROs. This means that        if prach-ConfigIndex is not signaled for small data        transmission, ROs configured for small data transmission are        shared with ROs configured for regular random access (i.e., non        small data transmission).

For 4 step RACH, if ROs configured for small data transmission are notshared with ROs configured for regular random access (i.e., non smalldata transmission):

UE determines the starting preamble index for small data transmission asfollows:

Starting preamble index (S)=0.

CB-PreamblesPerSSB-SDT (X) and ssb-perRACH-Occasion-SDT (Y) isconfigured/signaled (e.g., in the rach-ConfigCommon-SDT IE) by gNB forsmall data transmission using 4 step RACH.

UE determines preambles for each SSB as follows:

If Y<1: Preambles starting from S to S+CB-PreamblesPerSSB-SDT (X)−1 areused for small data transmission. In other words, X contention basedpreambles with consecutive indexes associated with the SSB per validPRACH occasion start from S.

If Y>=1, X contention based preambles with consecutive indexesassociated with SS/PBCH block n, 0≤n≤Y−1, per valid PRACH occasion startfrom preamble index ‘S+n·N_(preamble) ^(total)/Y, where N_(preamble)^(total) preamble is provided by totalNumberOfRA-Preambles-SDT.totalNumberOfRA-Preambles-SDT is the total number of RA preamblesconfigured for small data transmission.

-   -   In an embodiment, if prach-ConfigIndex is signaled for small        data transmission, UE uses the prach-ConfigIndex configured for        small data transmission to determine ROs. This means that if        prach-ConfigIndex is signaled for small data transmission, ROs        configured for small data transmission are not shared with ROs        configured for regular random access (i.e., non small data        transmission).

During the random access procedure initiated for small datatransmission, for each random access attempt UE first select SSB (SSBwith highest SS-RSRP or SSB with SS-RSRP above a configured threshold orany SSB if there is no SSB with SS-RSRP above threshold as specified inTS 38.321) and then preamble and RO corresponding to selected SSBwherein preamble is selected from set of preambles corresponding toselected SSB as determined above. UE then transmit selected PRACHpreamble and selected RO.

Case 2: Small data transmission is supported in the UL BWP using 2 stepRACH and not supported for 4 step RACH.

For 2 step RACH, if ROs configured for small data transmission areshared with ROs configured for regular 2 step random access (i.e., nonsmall data transmission):

UE can determine the preambles for small data transmission as follows:

Starting preamble index (S)=R1+R2, where N1 is ssb-perRACH-Occasion andR1 is CB-PreamblesPerSSB configured (e.g., in the rach-ConfigCommon IE)for regular 4 step random access, R2 is CB-PreamblesPerSSB configured(e.g., in the rach-ConfigCommon2Step IE) for regular 2 step randomaccess

CB-PreamblesPerSSB-SDT (X) is configured/signaled (e.g., in therach-ConfigCommon2Step-SDT IE) by gNB for small data transmission using2 step RACH.

UE can determine preambles for each SSB as follows:

If N1<1: Preambles starting from S to S+CB-PreamblesPerSSB-SDT (X)−1 areused for small data transmission. In other words, X contention basedpreambles with consecutive indexes associated with the SSB per validPRACH occasion start from S.

If N1>=1, X contention based preambles with consecutive indexesassociated with SS/PBCH block n, 0≤n≤N1−1, per valid PRACH occasionstart from preamble index ‘S+n·N_(preamble) ^(total)/N1, whereN_(preamble) ^(total) is provided by totalNumberOfRA-Preambles.totalNumberOfRA-Preambles is the total number of RA preambles configuredfor regular random access in the rach-ConfigCommon IE.

FIG. 22 and FIG. 23 are example illustrations.

-   -   In an embodiment, if prach-ConfigIndex is not signaled for small        data transmission, UE uses the prach-ConfigIndex configured for        regular 2 step random access to determine ROs. This means that        if prach-ConfigIndex is not signaled for small data        transmission, ROs configured for small data transmission are        shared with ROs configured for regular 2 step random access        (i.e., non small data transmission).

For 2 step RACH, if ROs configured for small data transmission are notshared with ROs configured for regular 2 step random access (i.e., nonsmall data transmission):

UE determines the starting preamble index for small data transmission asfollows:

Starting preamble index (S)=0.

CB-PreamblesPerSSB-SDT (X) and ssb-perRACH-Occasion-SDT (Y) isconfigured/signaled (e.g., in the rach-ConfigCommon2Step-SDT IE) by gNBfor small data transmission using 2 step RACH.

UE determines preambles for each SSB as follows:

If Y<1: Preambles starting from S to S+CB-PreamblesPerSSB-SDT (X)−1 areused for small data transmission. In other words, X contention basedpreambles with consecutive indexes associated with the SSB per validPRACH occasion start from S.

If Y>=1, X contention based preambles with consecutive indexesassociated with SS/PBCH block n, 0≤n≤Y−1, per valid PRACH occasion startfrom preamble index ‘S+n·N_(preamble) ^(total)/Y, where N_(preamble)^(total) is provided by totalNumberofRA-Preambles-SDT.totalNumberOfRA-Preambles-SDT is the total number of RA preamblesconfigured for small data transmission.

-   -   In an embodiment, if prach-ConfigIndex is signaled for small        data transmission, UE uses the prach-ConfigIndex configured for        small data transmission to determine ROs. This means that if        prach-ConfigIndex is signaled for small data transmission, ROs        configured for small data transmission are not shared with ROs        configured for regular 2 step random access (i.e., non small        data transmission).

During the random access procedure initiated for small datatransmission, for each random access attempt, UE first select SSB (SSBwith highest SS-RSRP or SSB with SS-RSRP above a configured threshold orany SSB if there is no SSB with SS-RSRP above threshold) and thenpreamble and RO corresponding to selected SSB wherein preamble isselected from set of preambles corresponding to selected SSB asdetermined above. UE then transmit selected PRACH preamble and selectedRO. UE shall also select PUSCH occasion from PUSCH occasions configuredfor small data transmission and transmit MsgA MAC PDU which includesmall data i.e., MAC SDU(s) for DRB.

Case 3: Small data transmission is supported in the UL BWP using both 2step RACH and 4 step RACH.

If ROs configured for small data transmission are shared with ROsconfigured for regular random access (i.e., non small datatransmission):

For small data transmission using 4 step RACH:

UE determines the starting preamble index for small data transmission asfollows:

Starting preamble index (S)=R1+R2, where N1 is ssb-perRACH-Occasion andR1 is CB-PreamblesPerSSB configured (e.g., in the rach-ConfigCommon IE)for regular 4 step random access, R2 is CB-PreamblesPerSSB configured(e.g., in the rach-ConfigCommon2Step IE) for regular 2 step randomaccess

CB-PreamblesPerSSB-SDT (X) is configured/signaled (e.g., in therach-ConfigCommon-SDT IE) by gNB for small data transmission using 4step RACH.

(Alternate) Starting preamble index (S)=R1+R2+R3, where N1 isssb-perRACH-Occasion and R1 is CB-PreamblesPerSSB configured (e.g., inthe rach-ConfigCommon IE) for regular 4 step random access, R2 isCB-PreamblesPerSSB configured (e.g., in the rach-ConfigCommon2Step IE)for regular 2 step random access and R3 is CB-PreamblesPerSSB configured(e.g., in the rach-ConfigCommon2Step IE) for small data transmissionusing 2 step RACH.

UE determines preambles for each SSB as follows:

If N1<1: Preambles starting from S to S+CB-PreamblesPerSSB-SDT (X)−1 areused for small data transmission. In other words, X contention basedpreambles with consecutive indexes associated with the SSB per validPRACH occasion start from S.

If N1>=1, X contention based preambles with consecutive indexesassociated with SS/PBCH block n, 0≤n≤N1−1, per valid PRACH occasionstart from preamble index ‘S+n·N_(preamble) ^(total)/N1, whereN_(preamble) ^(total) is provided by totalNumberOfRA-Preambles.totalNumberOfRA-Preambles is the total number of RA preambles configuredfor regular random access in the rach-ConfigCommon IE.

FIG. 22 and FIG. 23 are example illustrations.

-   -   In an embodiment, if prach-ConfigIndex is not signaled for small        data transmission, UE uses the prach-ConfigIndex configured for        regular 4 step random access to determine ROs. This means that        if prach-ConfigIndex is not signaled for small data        transmission, ROs configured for small data transmission are        shared with ROs configured for regular random access (i.e., non        small data transmission).

For small data transmission using 2 step RACH:

UE determines the starting preamble index for small data transmission asfollows:

Starting preamble index (S)=R1+R2+R3, where N1 is ssb-perRACH-Occasionand R1 is CB-PreamblesPerSSB configured (e.g., in the rach-ConfigCommonIE) for regular 4 step random access, R2 is CB-PreamblesPerSSBconfigured (e.g., in the rach-ConfigCommon2Step IE) for regular 2 steprandom access and R3 is CB-PreamblesPerSSB configured (e.g., in therach-ConfigCommon2Step IE) for small data transmission using 4 stepRACH.

(Alternate): Starting preamble index (S)=R1+R2, where N1 isssb-perRACH-Occasion and R1 is CB-PreamblesPerSSB configured (e.g., inthe rach-ConfigCommon IE) for regular 4 step random access, R2 isCB-PreamblesPerSSB configured (e.g., in the rach-ConfigCommon2Step IE)for regular 2 step random access.

CB-PreamblesPerSSB2Step-SDT (X) is configured/signaled (e.g., in therach-ConfigCommon2Step-SDT IE) by gNB for small data transmission using2 step RACH.

UE determines preambles for each SSB as follows:

If N1<1: Preambles starting from S to S+CB-PreamblesPerSSB2Step-SDT(X)−1 are used for small data transmission. In other words, X contentionbased preambles with consecutive indexes associated with the SSB pervalid PRACH occasion start from S.

If N1>=1, X contention based preambles with consecutive indexesassociated with SS/PBCH block n, 0≤n≤N1−1, per valid PRACH occasionstart from preamble index ‘S+n·N_(preamble) ^(total)/N1, whereN_(preamble) ^(total) is provided by totalNumberOfRA-Preambles.totalNumberOfRA-Preambles is the total number of RA preambles configuredfor regular random access in the rach-ConfigCommon IE.

FIG. 24 and FIG. 25 are example illustrations.

-   -   In an embodiment, if prach-ConfigIndex is not signaled for small        data transmission, UE uses the prach-ConfigIndex configured for        regular 4 step random access to determine ROs. This means that        if prach-ConfigIndex is not signaled for small data        transmission, ROs configured for small data transmission are        shared with ROs configured for regular random access (i.e., non        small data transmission).

For small data transmission using 4 step RACH, if ROs configured forsmall data transmission are not shared with ROs configured for regularrandom access (i.e., non small data transmission) and also not sharedwith ROs configured for small data transmission using 2 step RACH:

UE determine the starting preamble index for small data transmission asfollows:

Starting preamble index (S)=0.

CB-PreamblesPerSSB-SDT (X) and ssb-perRACH-Occasion-SDT (Y) isconfigured/signaled (e.g., in the rach-ConfigCommon-SDT IE) by gNB forsmall data transmission.

UE determines preambles for each SSB as follows:

If Y<1: Preambles starting from S to S+CB-PreamblesPerSSB-SDT (X)−1 areused for small data transmission. In other words, X contention basedpreambles with consecutive indexes associated with the SSB per validPRACH occasion start from S.

If Y>=1, X contention based preambles with consecutive indexesassociated with SS/PBCH block n, 0≤n≤Y−1, per valid PRACH occasion startfrom preamble index ‘S+n·N_(preamble) ^(total)/Y, where N_(preamble)^(total) is provided by totalNumberOfRA-Preambles-SDT.totalNumberOfRA-Preambles-SDT is the total number of RA preamblesconfigured for small data transmission.

In an embodiment, if prach-ConfigIndex is signaled for small datatransmission, UE uses the prach-ConfigIndex configured for small datatransmission to determine ROs. This means that if prach-ConfigIndex issignaled for small data transmission, ROs configured for small datatransmission are not shared with ROs configured for regular randomaccess (i.e., non small data transmission).

For small data transmission using 2 step RACH, if ROs configured forsmall data transmission are not shared with ROs configured for regularrandom access (i.e., non small data transmission) and also not sharedwith ROs configured for small data transmission using 4 step RACH:

UE determines the starting preamble index for small data transmission asfollows:

Starting preamble index (S)=0.

CB-PreamblesPerSSB2Step-SDT (X) and ssb-perRACH-Occasion2Step-SDT (Y) isconfigured/signaled (e.g., in the rach-ConfigCommon2Step-SDT IE) by gNBfor small data transmission using 2 step RACH.

UE determines preambles for each SSB as follows:

If Y<1: Preambles starting from S to S+CB-PreamblesPerSSB2Step-SDT (X)−1are used for small data transmission. In other words, X contention basedpreambles with consecutive indexes associated with the SSB per validPRACH occasion start from S.

If Y>=1, X contention based preambles with consecutive indexesassociated with SS/PBCH block n, 0≤n≤Y−1, per valid PRACH occasion startfrom preamble index ‘S+n·N_(preamble) ^(total)/Y, where N_(preamble)^(total) is provided by totalNumberOfRA-Preambles-SDT.totalNumberOfRA-Preambles-SDT is the total number of RA preamblesconfigured for small data transmission.

-   -   In an embodiment, if prach-ConfigIndex is signaled for small        data transmission, UE uses the prach-ConfigIndex configured for        small data transmission to determine ROs. This means that if        prach-ConfigIndex is signaled for small data transmission, ROs        configured for small data transmission are not shared with ROs        configured for regular random access (i.e., non small data        transmission).

Embodiment 4

Both 2 step and 4 step RACH are configured in the UL BWP. ROs are notshared between 2 step and 4 step RACH. Small data transmission issupported in the UL BWP. This UL BWP can be initial UL BWP or another ULBWP indicated by gNB for small data transmission.

For small data transmission using 4 step RACH, operation is same asdescribed in embodiment 1.

For small data transmission using 2 step RACH, operation is same asdescribed in embodiment 2.

Embodiment 5

For small data transmission using 4 step RACH, following parameters aresignaled by gNB. These parameters can be signaled inrach-ConfigCommon4Step-SDT IE or in rach-ConfigCommon IE.

-   -   startingPreambleIndex4Step-SDT (S)    -   ssb-perRACH-Occasion4Step-SDT (Y)    -   CB-PreamblesPerSSB4 Step-SDT (X)

If startingPreambleIndex4Step-SDT is not configured (in UL BWP on whichUE transmits PRACH for small data transmission), UE assumesstartingPreambleIndex4Step-SDT is zero. Network may not configurestartingPreambleIndex4Step-SDT if ROs for SDT are not shared with ROsfor non SDT. If ssb-perRACH-Occasion4Step-SDT is not configured (in ULBWP on which UE transmits PRACH for small data transmission), the valueof ssb-perRACH-Occasion4Step-SDT is equal to ssb-perRACH-Occasionconfigured for 4 step RACH i.e., in rach-ConfigCommon. IfCB-PreamblesPerSSB4Step-SDT is not configured (in UL BWP on which UEtransmits PRACH for small data transmission), the value ofCB-PreamblesPerSSB4Step-SDT is equal to CB-PreamblesPerSSB configuredfor 4 step RACH i.e., in rach-ConfigCommon (in UL BWP on which UEtransmits PRACH for small data transmission).

UE determines preambles for each SSB as follows:

If Y<1: Preambles starting from S to ‘S+X−1’ are used for small datatransmission. In other words, X contention based preambles withconsecutive indexes associated with the SSB per valid PRACH occasionstart from S.

If Y>=1, X contention based preambles with consecutive indexesassociated with SS/PBCH block n, 0≤n≤Y−1, per valid PRACH occasion startfrom preamble index ‘S+n·N_(preamble) ^(total)/Y, where N_(preamble)^(total) is provided by totalNumberOfRA-Preambles-SDT. IftotalNumberOfRA-Preambles-SDT is not configured,totalNumberOfRA-Preambles is used.

During the random access procedure initiated for small datatransmission, for each random access attempt, UE first select SSB (SSBwith highest SS-RSRP or SSB with SS-RSRP above a configured threshold orany SSB if there is no SSB with SS-RSRP above threshold) and thenpreamble and RO corresponding to selected SSB wherein preamble isselected from set of preambles as determined above. Mapping between ROsand SSBs is determined as in regular random access procedure. UE thentransmit selected PRACH preamble and selected RO.

For small data transmission using 2 step RACH, following parameters aresignaled by gNB. These parameters can be signaled inrach-ConfigCommon2Step-SDT IE or in rach-ConfigCommon2Step IE. Theseconfigurations are per UL BWP.

-   -   startingPreambleIndex2Step-SDT (S)    -   ssb-perRACH-Occasion2Step-SDT (Y)    -   CB-PreamblesPerSSB2Step-SDT (X)

If startingPreambleIndex2Step-SDT is not configured (i.e., notconfigured in UL BWP on which UE transmits PRACH for small datatransmission), UE assumes startingPreambleIndex2Step-SDT is zero.Network may not configure startingPreambleIndex4Step-SDT if ROs for SDTare not shared with ROs for non SDT. If ssb-perRACH-Occasion2Step-SDT isnot configured:

-   -   the value of ssb-perRACH-Occasion2Step-SDT is equal to        ssb-perRACH-Occasion2step configured for 2 step RACH i.e. in        rach-ConfigCommon2Step (of UL BWP on which UE transmits PRACH        for small data transmission); the value of        ssb-perRACH-Occasion2Step-SDT is equal to ssb-perRACH-Occasion        configured for 4 step RACH i.e. in rach-ConfigCommon (of UL BWP        on which UE transmits PRACH for small data transmission) if        ssb-perRACH-Occasion2step is not configured (in UL BWP on which        UE transmits PRACH for small data transmission).

If CB-PreamblesPerSSB2Step-SDT is not configured (i.e., not configuredin UL BWP on which UE transmits PRACH for small data transmission),

-   -   the value of CB-PreamblesPerSSB2Step-SDT is equal to        CB-PreamblesPerSSB2Step configured for 2 step RACH i.e. in        rach-ConfigCommon2Step (of UL BWP on which UE transmits PRACH        for small data transmission); the value of        CB-PreamblesPerSSB2Step-SDT is equal to CB-PreamblesPerSSB        configured for 4 step RACH i.e. in rach-ConfigCommon (of UL BWP        on which UE transmits PRACH for small data transmission) if        CB-PreamblesPerSSB2Step is not configured (in UL BWP on which UE        transmits PRACH for small data transmission).

UE determines preambles for each SSB as follows:

If Y<1: Preambles starting from S to ‘S+X−1’ are used for small datatransmission. In other words, X contention based preambles withconsecutive indexes associated with the SSB per valid PRACH occasionstart from S.

If Y>=1, X contention based preambles with consecutive indexesassociated with SS/PBCH block n, 0≤n≤Y−1, per valid PRACH occasion startfrom preamble index ‘S+n·N_(preamble) ^(total)/Y, where N_(preamble)^(total) is provided by totalNumberOfRA-Preambles-2 step-SDT. IftotalNumberOfRA-Preambles-2 step-SDT is not configured,totalNumberOfRA-2step-Preambles is used. IftotalNumberOfRA-2step-Preambles is not configuredtotalNumberOfRA-Preambles is used.

During the random access procedure initiated for small datatransmission, for each random access attempt UE first select SSB (SSBwith highest SS-RSRP or SSB with SS-RSRP above a configured threshold orany SSB if there is no SSB with SS-RSRP above threshold) and thenpreamble and RO corresponding to selected SSB wherein preamble isselected from set of preambles corresponding to selected SSB asdetermined above. Mapping between ROs and SSBs is determined as inregular random access procedure. UE then transmit selected PRACHpreamble and selected RO.

FIG. 26 is a block diagram of a terminal according to an embodiment ofthe disclosure.

Referring to FIG. 26, a terminal includes a transceiver 2610, acontroller 2620 and a memory 2630. The controller 2620 may refer to acircuitry, an ASIC, or at least one processor. The transceiver 2610, thecontroller 2620, and the memory 2630 are configured to perform at leastone operation including a combination of steps, which are not inconflict, illustrated in at least one of the drawings or describedabove. Although the transceiver 2610, the controller 2620, and thememory 2630 are shown as separate entities, they may be realized as asingle entity like a single chip. Alternatively, the transceiver 2610,the controller 2620, and the memory 2630 may be electrically connectedto or coupled with each other.

The transceiver 2610 may transmit and receive signals to and from othernetwork entities, e.g., a base station.

The controller 2620 may control the UE to perform functions according atleast one operation described above.

In an embodiment, the operations of the terminal may be implementedusing the memory 2630 storing corresponding program codes. Specifically,the terminal may be equipped with the memory 2630 to store program codesimplementing desired operations. To perform the desired operations, thecontroller 2620 may read and execute the program codes stored in thememory 2630 by using a processor or a central processing unit (CPU).

FIG. 27 is a block diagram of a base station according to an embodimentof the disclosure.

Referring to FIG. 27, a base station (BS) includes a transceiver 2710, acontroller 2720 and a memory 2730. The controller 2720 may refer to acircuitry, an ASIC, or at least one processor. The transceiver 2710, thecontroller 2720 and the memory 2730 are configured to perform at leastone operation including a combination of steps, which are not inconflict, illustrated in at least one of the drawings or describedabove. Although the transceiver 2710, the controller 2720, and thememory 2730 are shown as separate entities, they may be realized as asingle entity like a single chip. Alternatively, the transceiver 2710,the controller 2720, and the memory 2730 may be electrically connectedto or coupled with each other.

The transceiver 2710 may transmit and receive signals to and from othernetwork entities, e.g., a terminal.

The controller 2720 may control the BS to perform functions according toat least one operation described above.

In an embodiment, the operations of the BS may be implemented using thememory 2730 storing corresponding program codes. Specifically, the BSmay be equipped with the memory 2730 to store program codes implementingdesired operations. To perform the desired operations, the controller2720 may read and execute the program codes stored in the memory 2730 byusing a processor or a CPU.

While the disclosure has been shown and described with reference tovarious embodiments thereof, it will be understood by those skilled inthe art that various changes in form and details may be made thereinwithout departing from the spirit and scope of the disclosure as definedby the appended claims and their equivalents.

Although the present disclosure has been described with variousembodiments, various changes and modifications may be suggested to oneskilled in the art. It is intended that the present disclosure encompasssuch changes and modifications as fall within the scope of the appendedclaims.

What is claimed is:
 1. A method performed by a terminal of a randomaccess procedure for a small data transmission, the method comprising:receiving, from a base station, at least one synchronization signalblock (SSB); identifying at least one preamble associated with the atleast one SSB based on first information on a number of preambles perSSB and second information on a starting index, for one of a 4-steprandom access procedure or a 2-step random access procedure for thesmall data transmission; selecting a preamble from the identified atleast one preamble corresponding to an SSB selected from the at leastone SSB; and transmitting, to a base station, the selected preamble in aphysical random access channel (PRACH) occasion corresponding to theselected SSB.
 2. The method of claim 1, further comprising: identifyingthe second information on the starting index for one of the 4-steprandom access procedure or the 2-step random access procedure for thesmall data transmission.
 3. The method of claim 2, wherein identifyingthe second information on the starting index comprises at least one of:acquiring the second information based on a predetermined value for the4-step random access procedure or the 2-step random access procedure forthe small data transmission; acquiring the second information based onthird information indicating the starting index for the 4-step randomaccess procedure or the 2-step random access procedure for the smalldata transmission; acquiring the second information based on at leastone of fourth information on a number of preambles per SSB for a normal4-step random access procedure and fifth information on a number ofpreambles per SSB for a normal 2-step random access procedure; or incase that the random access procedure is the 2-step random accessprocedure for the small data transmission, acquiring the secondinformation based on the fourth information, the fifth information andsixth information on the number of preambles per SSB for the 4-steprandom access procedure for the small data transmission.
 4. The methodof claim 3, wherein at least one of the first information, the thirdinformation, the fourth information, the fifth information and the sixthinformation is transmitted on a control message from the base station.5. The method of claim 1, wherein, for identifying the at least onepreamble, in case that a number of SSBs per PRACH occasion is less than1, an index for the at least one preamble associated with the at leastone SSB starts from S; and in case that the number of SSBs per PRACHoccasion is greater than 1 or equal to 1, the index for the at least onepreamble starts from S+n·N_(preamble) ^(total)/Y, wherein S is thestarting index, n is an index of the at least one SSB, N_(preamble)^(total) is a total number of preambles used for the random accessprocedure and Y is the number of SSB per PRACH occasion.
 6. A methodperformed by a base station of a random access procedure for a smalldata transmission, the method comprising: transmitting, to a terminal,at least one synchronization signal block (SSB); and receiving, from theterminal, a preamble for one of a 4-step random access procedure or a2-step random access procedure for the small data transmission, in aphysical random access channel (PRACH) occasion corresponding to an SSBamong the at least one SSB, wherein at least one preamble associatedwith the at least one SSB is identified based on first information on anumber of preambles per SSB and second information on a starting indexfor one of the 4-step random access procedure or the 2-step randomaccess procedure for the small data transmission, and the preamblecorresponding to the SSB is selected from the at least one preamble. 7.The method of claim 6, wherein the second information on the startingindex is identified as: acquiring the second information based on apredetermined value for the 4-step random access procedure or the 2-steprandom access procedure for the small data transmission; acquiring thesecond information based on third information indicating the start indexfor the 4-step random access procedure or the 2-step random accessprocedure for the small data transmission; acquiring the secondinformation based on at least one of fourth information on a number ofpreambles per SSB for a normal 4-step random access procedure and fifthinformation on a number of preambles per SSB for a normal 2-step randomaccess procedure; or in case that the random access procedure is the2-step random access procedure for the small data transmission,acquiring the second information based on the fourth information, thefifth information and sixth information on the number of preambles perSSB for the 4-step random access procedure for the small datatransmission.
 8. The method of claim 7, wherein at least one of thefirst information, the third information, the fourth information, thefifth information and the sixth information is transmitted on a controlmessage to the terminal.
 9. The method of claim 6, wherein, in case thata number of SSBs per PRACH occasion is less than 1, an index for the atleast one preamble associated with the at least one SSB starts from S;and in case that the number of SSBs per PRACH occasion is greater than 1or equal to 1, the index for the at least one preamble starts fromS+n·N_(preamble) ^(total)/Y, wherein S is the starting index, n is anindex of the at least one SSB, N_(preamble) ^(total) is a total numberof preambles used for the random access procedure and Y is the number ofSSB per PRACH occasion.
 10. A terminal of a random access procedure fora small data transmission, the terminal comprising: a transceiver; and acontroller coupled with the transceiver and configured to control to:receive, from a base station, at least one synchronization signal block(SSB), identify at least one preamble associated with the at least oneSSB based on first information on a number of preambles per SSB andsecond information on a starting index, for one of a 4-step randomaccess procedure or a 2-step random access procedure for the small datatransmission, selecting a preamble from the identified at least onepreamble corresponding to an SSB selected from the at least one SSB, andtransmit, to a base station, the selected preamble in a physical randomaccess channel (PRACH) occasion corresponding to the selected SSB. 11.The terminal of claim 10, wherein the controller is further configuredto control to: identify the second information on the starting index forone of the 4-step random access procedure or the 2-step random accessprocedure for the small data transmission.
 12. The terminal of claim 11,wherein, for identifying the second information, the controller isconfigured to control to perform at least one of: acquiring the secondinformation based on a predetermined value for the 4-step random accessprocedure or the 2-step random access procedure for the small datatransmission, acquiring the second information based on thirdinformation indicating the start index for the 4-step random accessprocedure or the 2-step random access procedure for the small datatransmission, acquiring the second information based on at least one offourth information on a number of preambles per SSB for a normal 4-steprandom access procedure and fifth information on a number of preamblesper SSB for a normal 2-step random access procedure, or in case that therandom access procedure is the 2-step random access procedure for thesmall data transmission, acquiring the second information based on thefourth information, the fifth information and sixth information on thenumber of preambles per SSB for the 4-step random access procedure forthe small data transmission.
 13. The terminal of claim 12, wherein atleast one of the first information, the third information, the fourthinformation, the fifth information and the sixth information istransmitted on a control message from the base station.
 14. The terminalof claim 10, wherein, for identifying the at least one preamble, in casethat a number of SSBs per PRACH occasion is less than 1, an index forthe at least one preamble associated with the at least one SSB startsfrom S; and in case that the number of SSBs per PRACH occasion isgreater than 1 or equal to 1, the index for the at least one preamblestarts from S+n·N_(preamble) ^(total)/Y, wherein S is the startingindex, n is an index of the at least one SSB, N_(preamble) ^(total) is atotal number of preambles used for the random access procedure and Y isthe number of SSB per PRACH occasion.
 15. A base station of a randomaccess procedure for a small data transmission, the base stationcomprising: a transceiver; and a controller coupled with the transceiverand configured to control to: transmit, to a terminal, at least onesynchronization signal block (SSB), and receive, from the terminal, apreamble for one of a 4-step random access procedure or a 2-step randomaccess procedure for the small data transmission, in a physical randomaccess channel (PRACH) occasion corresponding to an SSB among the atleast one SSB, wherein at least one preamble associated with the atleast one SSB is identified based on first information on a number ofpreambles per SSB and second information on a starting index for one ofthe 4-step random access procedure or the 2-step random access procedurefor the small data transmission, and the preamble corresponding to theSSB is selected from the at least one preamble.
 16. The base station ofclaim 15, wherein the second information on the starting index isidentified as: acquiring the second information based on a predeterminedvalue for the 4-step random access procedure or the 2-step random accessprocedure for the small data transmission, acquiring the secondinformation based on third information indicating the start index forthe 4-step random access procedure or the 2-step random access procedurefor the small data transmission, acquiring the second information basedon at least one of fourth information on a number of preambles per SSBfor a normal 4-step random access procedure and fifth information on anumber of preambles per SSB for a normal 2-step random access procedure,or in case that the random access procedure is the 2-step random accessprocedure for the small data transmission, acquiring the secondinformation based on the fourth information, the fifth information andsixth information on the number of preambles per SSB for the 4-steprandom access procedure for the small data transmission.
 17. The basestation of claim 16, wherein at least one of the first information, thethird information, the fourth information, the fifth information and thesixth information is transmitted on a control message to the terminal.18. The base station of claim 15, wherein, in case that a number of SSBsper PRACH occasion is less than 1, an index for the at least onepreamble associated with the at least one SSB starts from S; and in casethat the number of SSBs per PRACH occasion is greater than 1 or equal to1, the index for the at least one preamble starts from S+n·N_(preamble)^(total)/Y, wherein S is the starting index, n is an index of the atleast one SSB, N_(preamble) ^(total) is a total number of preambles usedfor the random access procedure and Y is the number of SSB per PRACHoccasion.